I import a bmp file in my uv editor but I have no visual of my texture, if I import the same texture with a jpg file it works, blender can't show bmp file?
Because it is a weird Microsoft format better suited to bitmap images than UV maps? You can always convert it.
Yes I know but it specially to create model in hl1 so I must to use that, I see I can show bmp in uv editor but only 24/32 bits and nor 8bits (I need this)
use a supported format and replace the file afterwards, shouldn't be a problem. They may even differ in resolution, as UV mapping is relative to texture.
I'm sitting, waiting, wishing, building Blender in superstition...
Yes I've see that it's not a problem thanks