I've figured out how the RNG advances now. Showing the adress as 4 bytes instead of float values gives a whole number which is much easier to read. Through testing I can say it cycles between the value 0 and 32768 (256*128).
The formula that advances RNG is
("previous value" * 109) + 1021
So with this you can easily predict how it advances, although I'm still having problem figuring exactly how the drops behave. What I do know is that there's roughly two values every ten values which decides if an enemy should drop something. Interestingly it seems all enemies have a fixed item they drop, however if you don't have the sub-weapon they're supposed to drop, it won't drop anything at all.
Another thing I've noticed is that RNG necessarily doesn't advance just once. Sometimes it advances up to five times at once, for example during certain screen transitions (which I haven't looked into why yet).
Here's some RNG values which results in drops in case someone else might be able to find some sense from it.
What else have I investigated?
I've been trying to find a way to get the flares without solving the block puzzle, however with no success yet. I tried to corner glitch into the compartment where it is, but I'm a bit too far away to reach it. I'll continue to look into it in case I can find a solution at a later date.
I've also looked into the possibility to reach the bombs by glitching into the sloped ceiling at the entrance to the Tower of Ruin. Sadly there's been no success here as well yet. Not sure if it's due to ice physics decreasing your speed or if there's something else which prevents you from glitching into the sloped ceiling, however if you
can find a way to glitch up through the roof, you'll be able to get the bombs without any more problem.
