Just to add to this, I'm using v3.06, and this just happened to me as well. Seth's method of deleting the cmpro.ini fixed the problem as well (I kept a copy of the .ini, if you'd like to take a look at it Roman).

The problem is exactly as Seth describes, you type a filename to create a fixdat, click ok and nothing happens, no prompt for system name, nothing.

> > I found the error...i delete the cmpro.ini...and now
> > at next start from the programm ... i can save fixfiles.
>
>
> :O) thanks for letting me know
>
> Roman Scherzer
> ClrMamePro
>