Well, I wouldn't quite call it a custom uniform.
Anyways, I owe a great deal of thanks to son_ix for figuring out the fubar'd batch file. Anyways, until the auto-batchfile thing gets fixed, here's the procedure:
1. Create/modify texture, save in source folder (specified in editor prefs) as TGA
2. In editor, create new item under "Textures" tab
3. Click "srcname" and locate your TGA file
4. Select image type (dropdown box) *
5. Select format (dropdown) #
6. Right-click on the new texture (left panel) and hit "export".
6a-c are for those of you whose path to Silent Storm contains spaces
6a. Go to your system temp folder and locate "texture_export.bat"
6b. Edit the file: enclose all paths in quotes, and change any "" to single backslash. Save and run.
6c. Back to the editor, right click on the texture again, and hit "export (overwrite).
7. Et voila. Brand spanking new texture for you to play with. Now in order to use these textures on models and such, you will have to create a new material.
Most times you can get away with "ordinary". The only other one I've played with is "bump". Essentially what that does is convert a greyscale bumpmap into an RGB normal map for use in the game. If the file you're importing is already an RGB normal map, then just import as "ordinary"
The first 4 sets of numbers simply indicate the number of bits per channel of RGBA. The next 5 instruct the editor to convert the textures to DXT before importing
Cheers, and let me know if you need any clarification.