What is it you wish to make a transmap of? You mention wanting a transmap for a glass object. What's the object? A beer mug, a window? You need the object first. You decide. UV mapper gives you the template you need to locate where a map (texture, bump, or transparency) will cover your object. Once you've got your template, decide to what part of your object you'd like to apply a degree of transparency. Create a greyscale image that covers those areas in a image editing program (i.e. Photoshop) using the template as a placement guide. As you can see from the example above, black areas appear transparent, white opaque. Use the materials editor to apply the transparency map to your object. (The option to do so is in the lower right corner of the editor) You can then decide the level of transparency using the sliders in the materials editor. Experiment. Good luck...