I think I'm late to the party for this one.

Finished first two levels. Level 2 did kill me once, but it wasn't the hack-fest I read about. Didn't see anything about ...
Spoiler: show
... having to push two blocks in one room. Perhaps that means I missed something; so far I got the blue candle, the raft, and the first bomb upgrade from the levels, and the white sword and two HCs from the OVW.


Found Level 4 easily enough; not sure if I need to buy a key before entering, or whether I should have an extra key from Level 3.

Currently stuck looking for Level 3 (as well as 5,6,7,8 ... 9 was easy to find), as well as the blue ring and power bracelet.