Yeah, that's what I did. I'm glad it's still completeable at least. The conversion fucked up ceiling collisions (for example it should be possible to get past those two bugs in the cave without getting hit, but it isn't in this build) and the way the counters are drawn when you get a second row of HP, but at least I can almost pretend that ledge thing is a bad puzzle.

The protection, I believe, reduces the damage you take from each enemy by 1 bar per tick for each level of it you have. Although the effect seems small, it adds up to a huge reduction even with just a couple of levels so it's another way to grind for tough fights, which is important because I didn't emphasise being able to escape with spacebar enough.