So you are using a custom texture? Make sure that the pathname is correct. For example if you imported the blp make sure it's war3mapimported/whatever or whatever path name you gave it.
Delete the model and skin you have on your map.
Close your map (Save too) And re-open it. Now import the model (don't change the path) and import the skin. Change the path of the skin, just remove the wc3mapimported\.
SAVE IT
Close your map, and re-open it.
Ghan has said he has fixed this. Monovertex please confirm this fix. This was only a problem with people that had signatures in the upper levels like not the special members but the respected members.