Thank you RAMWolff for your suggestion, hope that Renderosity will put it on the list.

Concerning Transparency (cornea, eyeslash,...), just plug the Map in the transparent channel and set to 100%. Then hit shortkey "r" and "G" to see the effect. Concerning bump maps, you can easily create them: Import your color diffuse map in the map tab, rename it "name_Bump", plug it to the bump channel and back in the map tab, select it, right click and turn it to grayscale. Your base bump is created. You can add some details with your own brushes. You can do the same for specular and blur it with the blur tool.

Hope it helps,

Best regards