Same dude, I really wanna try out this category :)
Like WanderAgro mentioned, take a look at that post.
Basically, the 2 free + easy ways are point a camera at it, or use switch's 30 second captures.
The way most people who don't wanna bother with a camera setup do it (or those who like direct footage capture) just buy a HDMI capture card of their choice.
Capture cards handle the heavy lifting. It's like how when you plug in a headset, your PC doesn't get laggy or anything because the headset does the work. That being said, if you're in the USA, the mirabox is like $50 (my capture card of choice).
@khasinteb first off, I'd ask in the sm64 forums since they'll know the real answer, but if I'm remembering right it's because you're on the "patched" shindu (not sure that that's what it's called)? sm64 version.
Like the one where BLJs are patched, no more "so long gay bowser", and that weird tree thing you're mentioning. The changes made just make the game less fun for speedrunners, which is why 3d all stars runs have their own boards.
While roms (such as apks) definitely aren't illegal if you create them yourself (aka game backups), I'm pretty sure downloading a game you're supposed to pay for is definitely piracy, if not illegal, although it is in a very legally grey area.
Depends on what it is.
Generally I don't think anyone has an issue with you enabling these cheats, but the problem tends to be that they can drastically change a speedrun and most times make them comically easy or unfun. That's why there's generally a category extension or subcategory for cheats enabled (or at least should be IMO) when it exists in games.
Pro Tip: anyone including @The_Catanator can play these games :)
You kinda just need a lot of time, not sure what skills are involved moderating on src.
Custom maps on leaderboards cause tons of issues across the board whenever they've been allowed in other games. It's very unlikely that we allow them here. You could try to request a board for a specific pack or something though and make boards for that there.