I have some invisibility textures, but they won't work, since they're fire effects. I think there might be one in nalifx, but I haven't checked yet.
"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram
Technically, you have to load unrealed, open a texture pack, and then check the name of an image, maybe "UnrealI.beltfx.invis" or something, so you put that in your user ini after "skins=" (make sure you clear what's after face=).
If you need some more assistance, feel free to reply
"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram