The file remains empty after copying whole folder to a flash drive. When launched on another PC, my settings is not there.

How does the Dexpot know I created the file? When will it fill in my settings?

I've read this FAQ Is there a portable version of Dexpot?, I did create the file, but what now?

To make a regular installation of Dexpot portable, create an empty file called portable.ini in the Dexpot program folder (usually C:\Program Files\Dexpot).

I would too be very much interested in why it is not possible.