[Bug-gnubg] How to change/set the preferences storage location? / Make GnuBP portable?

[Ben Stover]

Hello,
I installed successfully GnuBG on a computer.

Then I copied the installation directory to an USB stick.
When I play this USB based GnuBG on other computers then I can do this but the 
preferences cannot be saved.

When I switch off e.g. the sound then the sound is automatically enabled the 
next time
when I start GnuBG again from USB stick.

Where are exactly the preferences saved?

Can I change somehow the location of the settings storage?

Can I e.g. put the preferences into an gnubg.ini in the installation directory?

Ben