Hide sculp image preview inside SL prim editor

I made some sculp objects (using blender) which i want to sell as free to modify. Unfortunately, SL prim editor totally expose my sculp images as it shows 128X128 image preview inside the prim editor. Since my maps are 128px wide, a simple print-screen of the editor expose my sculp map image.

For a normal textures, this is not a problem. 128px thumb is worthless, but for sculptures, 128 X 128px preview thumb exposes the source.

Is there a way (maybe a PNG header of embedded preview thumb) to display something else as preview, inside SL prim editor?

Thanks

In the LAYER properties of the image editor you need to ADD an ALPHA CHANEL to the LAYER.

Do not add an extra layr, but goto layer properites and chanels.

Detailed instructions how to do this are in this thread:
/8/6a/248258/1.html
NOTE: In the original program the TGA file will still look like the normal sculptmap, but after you upload it to SL, the alpha channel will be on top and it will look something like this:

Many thx, madddyyy & Malia