Grimrock

I tried multiple lever combinations and can't get more pits to close so I can proceed. Levers I found:
- the one at the start obviously,
- the one closing the pit to the wisp spot.
- The two levers there.
- Then two levers reachable with one of the wisp spot levers.
So I went on and found two small buttons opening gates. Closed a pit through the left gate with a secret button, found a box. Could not proceed further through the right gate because of open pits. There is also one open pit in the left room after the box that blocks my way. And on the other side of the hallway near but not at the wisp spot there are two pits I could not close.

Should I have 2 keys before I go into the palace fireball room ?

no, one key is enough, but depending on the version you are playing currently you need to open the door opposite of the hallway first. You won't get hit by the fireballs if you follow the ogre dance from a note

Can't remember exactly. It's possibly either dropped by a fire elemental or it is found in an alcove in a secret passage. Or maybe it was in a sack in the fire hall? I am sure it is on the same level though.

Got it thanks.It's in a bag in the fireball room but you have to do the Ogre dance first to get it.

I have been missing a lot because I did not go through the portal. I did that now and I'm in the area where there is a cube running after me. I'm running around but I don't know what to do and it's hard not to get lost. Is it possible to trap the cube somehow? I think it is as I could have let it follow me into the start area and then I could enter the cube area with the gates closing and I would have locked the cube out. But it's too late for that now. The start area seems not accessible any more because the gates are closed. Maybe you can give me a small hint?