Well, I don't need to explain Sandboxie. It's a way to make installations and/or run apps complete isolated from host system.
Now the interesting part:
After using Sandboxie... you have a file "reghive" in your sandbox folder (default: C:\Sandbox\USERNAME\DefaultBox)
This file contains all registry changes done in your sandbox.
Download DumpHive and extract it.
Copy the reghive file from above folder to dumphive folder and execute the batch file. You will have a new reghive.txt file which is nearly the same like a .reg file.
