Editing with Paint?

Is it possible to edit with Paint when editing .REZ files or is Photoshop a must?If Photoshop is a must do I have to buy it or is there a way around it? Would the free trial version of Photoshop work sufficiently?

there is a post ehre already on how to get photoshot CS4 for free -.-' and and i dont know if paint takes DTX files sorry an dyeah free trial will work

You can use GIMP or Paint.net, they are free

dtxconvert(nexon>lithtech)
Use DEdit and convert the dtx to tga
edit the tga (ms paint, GIMP, etc)
Use DEdit to convert back to dtx
dtxconvert (lithtech>nexon)

all those programs are free, just search for them. if you still cant figure it out, google search: "AVP Skinning tutorial" or something