Significance of Commander Keen in Map 29 PL2?

Does anyone know what exactly is the purpose of the commander keens in Map 29 Ticket to Eternity in Plutonia 2?

What triggers their 'compartments' to be opened? What happens if they are all opened?

Just wondering...

Oh, there is a super-special secret. I think I viewed it in-nomonsters and cheats, too complicated to find it the "legal" way. It is worth seeing! Another funny thing: there is an invulnerability in MAP17 and a glowing text "HI!" I don't know if it is possible to grab this invul in single-player(?)

Yes it´s possible to reach the invul place with Strafe50 run over the barrier (and a bit of luck :-)

Anyway, about the keens in map29, there are 6 (or 7?) keens placed around the whole map. They are always hidden in some small secret room. If you find one, one small ´compartment´ near the start is opened. If you shoot all skull switches you are allowed to enter a supersecret room.
Basically the same principle is used in Speed of Doom map31 to open the super secret exit. But it´s much easier there since all the keens around the level are visible without opening any door or whatever.

Thanks Gusta.

So if you find a Commander Keen in the level and shoot it, the corresponding compartment will open? What skull switches are you talking about? The ones behind the Keens?

Yes exactly, I mean the skulls behind the Keens in compartments. Anyway, have you found any of those Keens around the lev?

Well one time, after playing the level for some time, I ran back to the beginning to check up on them. I noticed that the second keen had been exposed. I do not remember seeing a keen in the level and I did not pay attention to what I had been doing to trigger it, so I have no idea how it happened.

Have any ideas? Or do you know where the other ones are?

Thanks again.

If you wish, I will record a demo for you and reveal where all of them are.

Wait... this just occured to me... (I am a little slow...) You are THE Gusta?

If you want to record it, thats cool. I have always been enthralled with Ticket to Eternity. Probably one of my favotite maps. Second to Arch-Violence. Great Maps! But anyways... if you want to record a demo that would be really cool.

Lol at my earlier questions... "Have any ideas? Or do you know where the other ones are?" Ha ha ha ... der...