Ocra makes windows built-in firewall ask to unblock ruby each time target exe launched

I wrote an utility that send messages over the Internet. I packed it
into exe file with ocra. Each time I launch that exe, firewall asks me
whether I want ruby to be blocked or not. I know that happens bacause
each launch target exe file unpacks ruby.exe to the temporary dir. That
directory is different each launch.
I’ve found a solution which imply patching .c file in ocra source and
recompiling ocra. Is there a ruby way to make temp dir path permanent?

Thank you.