The toughest part of this level is to get across a large pool of lava that seems to block the way. Within the pool is an H-shaped platform that you can raise to get across (see below), but you can also get across by jumping down into the lava, and grenade hopping up on the other side.
However, if you rather raise the platform, you need to go to the room with the single column. Behind the column (besides some wasps) is a passage to another room, which leads to a stairway to where the switch for the platform is. This entire route, thou, is filled with route, and the stairway is filled with wasps as well, so this could be tricky.
However, you can bypass this route to get to the platform switch by grenade jumping to the hallway within the column room. A backwards grenade jump seems to work best (withouth taking damage).
As you will be hit with lots of wasps for any route, you may want to run through the passages back to the shield regenerator after awakening the wasps. This will help spread the wasps throughout the level and will make it easier to pick them off.
There are no known secrets on this level.