Yes. For example. I open the Crestron provided Destiny template in VTPro and Save As a new name, but as a .vtt file and then can change out graphics and have my own template.

In learning how to do this I have probably 4 or 5 different template variations of Destiny for the PTX3 and multiple versions of each variation. I've finally settled on one and am in the process of duplicating the graphics for the other interfaces we use. 

It's not easy and there isn't any real help for doing it. I basically use Destiny b/c most of the template data is done and it has lots of data in place that you can review to learn from in a backwards engineering type sense.