Finally, almost a year after starting on this project, my Random Map Scripting Guide is basically feature complete. It is maintained as a Google Doc, so there will be updates and possibly even new sections, but at the moment, I have covered everything I wanted to.
Take a look if you are interested:
Thank you so much for putting that together. It will be an invaluable resource. 
Amazing great job! 
Is there any officially maintained source of all the RMS scripting commands, or would I have to parse through every changelog to find new commands?
There are official sources, but they aren’t as well maintained and don’t list everything.
There is also the non-localized-key-value-strings-utf8.txt file, which does have everything, including a few things that don’t work.
Doesn’t appear to acknowledge the nonsense of map size names. I always forget the answer and always have to test for myself to figure it out cause no online source gets it right.
All of these exist or existed, 2 of them had name changes when DE came out, change is shown in game but the RMS syntax remained with old name. I think its with Normal and Huge, something was not right with the naming convention, it’s something weird like Normal is actually Large now and Huge no longer exists or something like that, I wrote it down but I lost it.
Tiny
Small
Medium
Normal
Large
Huge
Gigantic
Ludikris
Nothing has changed, but you are correct about the inconsistency. I do make note of it, for example here:
normal is LARGE_MAP
large is HUGE_MAP
Hey there. I am reading your guide, in the objects section. I want to make a map for the King of the Hill game, where you can find other (small) buildings around the Monument that are converted, just as the Monument. Is it possible?
Yes, this is possible. set_building_capturable is what you should use for that.
Hi. I do not speak English. Your document format is untranslatable by Google. A way to change that? 
Click on the first “CLICK HERE” and then have google translate that version
Zetnus have you worked out a way to deploy to DE and ROR RMS in the same Zip file?
I just need the correct structure so the maps show up in game.
Yes, I think you need to use
modes\Pompeii\resources\_common\random-map-scripts