It seems like it's been a while since anyone's posted here, but I'm interested in speedrunning the game. I used to play it as a kid on arcade machines, and now own a Famicom cart of it. My issue is I can't find anything on RNG manipulation of each vaults content. Does something like this exist?

On the emulator, I get a good RNG for the 1st stage if I start the game in the 1st or 3rd frame. I hold "select" (to skip the splash animation), press reset, and mesh "start" for that.
Other stages are extremely random as far as I know.
/google translate.

Not much of the RNG manipulation. Mostly but not ALWAYS 100% on the 1st stage can be manipulated to stay the same as usual. From 2nd stage and after, will be a reset-fest till you get the right manipulation you wanted. For instance: The first cave level you fall down at the start. The first door you destroy, the one under the pipe platform after you jump over those 2 pits, is the only one door that needs to manipulate to get the goonies to spawn. If you're going for the skip. If not skipping the stage, you might want the goonies last on the way to exit, if you can get the keys on first screen and nearby the doors and on the way to get the last goonies before heading to next stage.

If I remember I made a grid of the items and goonies that spawn to know which one is which in each door location. I think I still have it....somewhere.