Re: unable to start unetbotin
I seem to remember having the same issue when using the later version downloaded from sourceforge.
In the end, on Fedora, I wound up installing the Fedora version with yum install unetbootin
It's an older version, but worked for me where the sourceforge version didn't.
It is helpful if, when posting questions, you mention where you got the software--that is, if this is a Fedora package or the pacakge from the sourceforge unetbootin site.