I'd like to be able to upload texture with transparent parts on dq texture, because when i add a tex with a transparent background it's just black in game and it's shit. That's a detail but still.

I have been able to upload full clear textures, i don't think parts being clear should be a problem. Are you using a file format that supports clear/invisible parts?

I used gif for transparent parts not working and with pgn too

But with other parts of the tori it's ok

i had a completely invisible dq texture back then but i kinda forget how i did it, try making the transparent parts black