Hello Thales,
there a few you tube videos about the unfolder script and its potential:
https://www.youtube.com/watch?v=b9gR4Om9tIQ
Your request reveals some weakness of the script, i would also prefer a preview for the unfolded mesh, but consider please that addam has developed his script beside its studies. I tried to write such a script for myself before i knew Addams script and i failed!!!!
In so far i have many respect for Addam and his script.
The only workaround is, to use the kartonbau script. This offers the option to unfold the mesh and export it in the next step. But this script doesn't has the ability to unfold textured meshes, respectively to export textured meshes!
Okay Thales i hope i could help you
Thomas