Now another noobish question:
As far as I have gathered by now, if you add/change certain things in a ROM, you need to find some more room for them.
My question is:
Which changes to the ROM require extra space? And how much extra space is left on a ROM until I have to delete other things?
I know that adding Pokémon to a Trainer's team needs more space, as does adding Attacks to a Pokémon's Move list. But what else?
And my other (probably equally noobish) question:
Where can I find stuff to delete if I need more space?
I have noticed that data for all trainers in Ruby/Sapphire/Emerald is in the FireRed ROM, I assume I can savely delete all of those to make room, yes?
Thanks for the help so far, I hope I'm not bothering you with my questions.
You should have enough free space left in your ROM to make your hack without having to delete anything.
Even if you run out of free space, you can easily expand the ROM using XSE.