This part of the game can be confusing, and sometimes the last straw for anyone who has been struggling through this game.  My hope is that this little bit of direction will help you to get to the boss fight at the end of the game with a sense of satisfaction at having completed a very difficult game.

You need to start in the purple tunnel for this walkthrough.  To get there, let’s start back where the two vampires were torturing the priest on a spit and one other vampire is running around ready to attack.  As soon as you jump from the wooden walkway, the roaming vampire comes to attack.  Run past him on your right and under the wooden structure.  Run and jump onto the rock formation to your left.  You are safe here, so take a look around.  To your right, you can see the two vampires still having the bon fire.  To your left is a wooden gate.  You need to walk straight ahead and jump to the ledge right in front of you.  When you enter this cave you are in the purple tunnel.  Let the game begin.

Purple Tunnel

Save your game.  The first thing that you see is a closed bamboo gate with a guard, health and a level map behind it.  Walk to your left and turn right at the intersection.  Take the first left and enter a room with rocks.  Have Mr. Hyde pick one up (one of the middle ones), return to the barred gate and toss the rock to break it open.  Enter the room, kill the guard, take the health and study the map.  The map shows three rooms surrounding a main central room where the boss fight takes place.  Each room is connected by a different colored tunnel and also to the central main room.  The library is on the bottom right, the larder is the bottom left, the worship room is the very top and the central room is the dormitory.  The purpose of this level is to destroy three main pillars, one in each of the three surrounding rooms and retrieve the Book.  We are going to head down the purple tunnel to the library.  Leave the map and go back towards the room with the rocks.  Walk past this room and continue till you can see the tunnel split up and down.  Take the “up” walkway, jump across the chasm with falling rocks and run past the vampire and straight into the library.  One note here: this looks like a dead end but is not.  There are dead ends but they look like the surrounding tunnel's walls.

The Library

Save you game here.  Do a standing jump to the platform in front of you.  Smack the green light to break it.  Line Mr. Hyde up on the left side of the platform and make a running jump to the next platform with the lady vampire on it.  If you stand next to the main pillar you might be able to smack her without taking any damage.  If you kill her, go get the health first, if not, just run past her to the right and climb up onto the small platform in front of the green light.  Whack the light to break it and you get a cut scene of the vampire platforms falling.
You are now standing on a ledge.  Walk two paces, turn around and jump to a higher level.  Turn around and walk clockwise till you get to a painted beam in your path.  Pull up onto it.  Walk up to the center pillar and jump to the cross beam on your left.  Walk the beam all the way to the wall.  There are rocks here to pick up.  If you see no rocks check the other beams.  Some rocks are hard to see and blend in with the wall and some in other rooms are different colors.  You need to throw 3-4 rocks at the central pillar to destroy it and the painted pillar slides out of sight and into the dormitory.  Walk back to the rocks and you should be able to save the game.  Jump the broken beams until you are on the opposite one from the rocks.  You can climb down here.  Walk this ledge until you come to the narrow part and let yourself down.  If you are having trouble doing this, try running off the edge and you will land on the next ledge.  From here, do a standing jump, then a standing jump, then a standing jump and then a drop down.  Turn around and run off the edge to the tunnel ledge.  Enter the tunnel and you are back at the purple tunnel.

Purple Tunnel Second Time

Save your game.  Retrace your steps to the start of the game.  In other words, go forward, jump across split and chasm till you get to the rock room.  Grab another rock and go to the intersection, at the beginning of the level, and turn left to return to the gated room.  Use the rock to bash the gate and get the health.  It has magically reappeared. Go back to the intersection and turn left and enter the Larder room.

The Larder

Save your game.  Do a standing jump to the ledge on the left.  Walk to the end of it and do a standing jump to the next higher ledge.  Turn around and jump straight up, then push the forward arrow key to grab the beam and pull up.  This is the beam with the rocks.  They are the same color as the wall and you must get very close to them on the left side to get Mr. Hyde to pick them up.  Use four of them on the central pillar to destroy it and the painted beam will slide out of sight and into the dormitory.  Two down, one to go.  Turn around and walk back to the rocks.  You can save your game.
You can get down the way you came up if you run off the beam to land on the end of the closet/highest ledge. (If you can’t do it, then go across the beams to the brightly lit ledge and go down that way).  Run off the next ledge or hang and drop to the green beams and enter the purple tunnel a third time.

Purple Tunnel Third Time

Save your game.  Go forward past the rock room to the split up and down.  This time, go down.  Drop to the ledge and then to the tunnel floor.  Kill the guard.  Stand in front of the ledge with your back to it and take about 16 steps forward.  Turn around and look up to the ceiling.  Pull up and get the health.  Drop back down and continue in the same direction.  Drop down to the next ledge and tunnel then continue forward into the larder again.

The Larder Second Time

Mr. Hyde needs to go to the left.  Walk off the end of the ledge and go that way.  Walk past the burning post and pull up onto the very next ledge.  Walk forward to enter the orange tunnel.

Orange Tunnel

Save your game.  Walk forward past the split “up”, kill the vampire and get the health from the wall.  Continue down the tunnel, run and jump both chasms and stay in the middle to avoid the grabbing hands.  Walk to the end and enter the dormitory.

Dormitory

This is a large room with a pit in the middle.  There is a health on the floor but save it for later unless you absolutely must have it.  Walk to your right and enter the next tunnel.  This is the gray tunnel.

Gray Tunnel

Save your game.  Jump onto the rock in front of you and pull up into the higher part of the tunnel.  Run past the guard, jump the chasm and run to the end of the tunnel, into the worship room.

Worship Room: Going Up

Save your game.  You start out in the Devil’s mouth on his tongue.  You will be coming back this way again as you need to get back to the Dormitory for the boss fight and end of the game.  Walk off the side of the tongue, drop down and drop down again to land in the pool of blood.  Go forward to the flaming gargoyle and pull up onto his head.  If you can’t do this, pull up onto the smaller ledge and jump to the gargoyle.  Jump up to the ledge to the right of the gargoyle and pull up to the next ledge.  Turn around and do a standing forward jump to the next highest ledge then pull up onto the gargoyle.  Jump to the toothy ledge to the left of the gargoyle, then left again to the next gargoyle.  Walk to the other side of the gargoyle and jump forward to the brown rock formation.  Jump quickly up to the top and pull up onto the next gargoyle.  Turn around and stand on the right wing of the gargoyle and pull up onto the green beam.  Jump to the toothy ledge and then the small red ledge.  Turn around and pull up onto the gargoyle and turn around again.  Jump to the rock and pull up onto the brown beam.  Walk or jump to the beam on your right (the one with rocks on it).  Save your game.  Destroy the central pillar with four rocks and once again save your game.

Worship Room:  Going Down

Walk to the end of the beam and jump to the beam on your left.  Drop down to the rock on the left side of the beam and jump to the gargoyle.  Drop to the toothy ledge below or use the small red ledge to get there.  Run off the ledge to land on the green beam to the right.  Drop down to the gargoyle and drop to the rock below that.  Walk to the other side of the rock and run off to the gargoyle.  Jump to the toothy ledge and pull up to the highest ledge above the next gargoyle.  Drop down to the gargoyle or use the smaller ledge to get there.  Drop to the small ledge to the left of the gargoyle, then run off to the next ledge or hang and drop, till you get to the last gargoyle.  Drop to the red beam by the blood pool and walk to the left of the Devil’s head.  Walk to the beam beneath the head and approach the book.  You turn back into Dr. Jekyll.  Save your game.  Walk into the red pool and pull up onto the Devil’s chin and then pull up onto the tongue.  Turn and enter the gray tunnel again.

Gray Tunnel Second Time

Save your game.  Run and jump over the chasm.  Run past the guard and run off the end and onto the ledge.  Drop down and continue the same direction and enter the dormitory for the final fight.

Dormitory End Game

Save your game.  Walk to your left and climb the slanted beam.  I did not touch the last health just yet.  Walk all the way up to the third beam and save your game.  Pull up onto the top ledge and watch a cut scene.  Save your game immediately after the cut scene.  You are now Hyde and need to pick up the boulders laying around the ledge and toss them at the three center beams.  It takes three boulders to destroy each beam.  The Boss moves in a clockwise direction and you can pretty much avoid him at first.  Stay away from the shining green fourth beam.  You cannot destroy it and it will do you harm.  The boss moves faster as you do damage to the beams.  If you are really good, you can beat the boss and walk down the last shiny green beam to get Laurie and watch the cut scene.  Happy ending.  I, on the other hand had to descend down the slanted beams to go get the other health at the bottom.  (Be careful leaving the ledge to get on the slanted beam.  It is very hard.  Hang and use your left arrow key to move to the beam and Hyde will stand up.)  I entered the red cave to look for more health but found none.  I reentered the dormitory and the boss was gone.  After I climbed back up, I just walked over to Laurie’s cage and the end cut scene started.  Happy ending too.

Congratulations!