also, on page 6 where you mention other engines you could link to EFPSE which is similar to RGM but a major improvement in just about every way and can be a great way to make the transition from RGM to something like Unity easier
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Oooooh! That's fantastic! I had heard some rumblings about EFPSE late last year, but I had no idea it got released. Looking at its features, I'm impressed by how it builds upon RGM and makes many things more intuitive. That being said, I'm still glad I made this guide, as it still felt like something that needed to exist for those who want to give it a try.