While it is true that RPG Maker is limited, you just need to get creative with it! Basically I'd say know what you want to do with it and then start searching scripts that can help you achieve it (google is my best friend with this). If you're familiar with scripting and the engine's language you can do wonders with it, but if you're like me and only know some of it, you can probably try modifying existing scripts to do what you want. I don't really know any tutorials (I'm more of a learn by example kind of person, so all the modifying of the scripts I did were done by trial and error), but if you're looking for scripts I recommend starting with Yanfly, Yami, Himeworks, Galv and others (seriously, google is all you need friend), they have a vast selection of scripts that are, for the most part, free to use!
Thank you again and good luck with the game jam!
(PS: Yeah but those are in dollars isn't it? If you convert them to my local currency weeeeell it's not that cheap, plus shipping is a pain. I would need to find them in a physical store for me to buy haha i cry)