When I create a kit (f.I.a oicw + frags) and edit it into the game it works, but the images of the weapons in game are blanc, how do I set them up?

Thanks in advance

You need to create those kit images by combining parts of existing images or making completely new ones. You would need Photoshop and the photoshop plugin to make it.
Your kit is the oicw rifle (not the g/l?) plus hand frags? I could try to bash something together if you don't have photoshop.

I have photoshop 7 and 8

Alright, first you need to install the photoshop plugin from the IT disk. Open up the kit icon files with the oicw and frags (any kit with frags will do). They will be in the shell/art/kit subfolder.
The images are on an alpha channel, so go to the channels tab, copy the grenade image and paste it on the oicw image in the middle slot. It will probably paste as a second alpha channel, so merge the two. then save as a new kit icon.

In your kit file, enter the name of that image for your kit icon.