Region map editing gen IV

[DunkyJay]

I was just wondering if there was any info on where sprites and scripting data for the region / town map in gen IV roms and whether there were any tools to be able to extract, edit and reinject them into the rom? I’m just starting out on my rom hacking journey so apologies if this breaks any etiquette and any and all help and advice will be greatly welcomed. I’m happy to get my hands dirty on figuring the whole thing out but thought someone may be able to point me to a good starting point.

Thanks in advance!