(Yeah, I've been advised to avoid the RTP as well, but I'm working with some plugins that won't run without them. I'll be sure to post screenshots when I can, but the maps I'm using are barely presentable at the moment. I like to use parallax maps, so most of what I have so far is just the tilesets scattered about to show what's passable and what isn't. So, a total wreck.)
(I'll be sure to rope some people into playtesting, especially because I'm close to being finished with the first puzzle. Thank you so much for the advice! Good luck with the Jam!)