Windows Firewall and portable apps?

I run portable applications often (programs you run directly off of removable
media, e.g. USB flash drives) and it seems Windows Firewall doesn't always
handle them correctly. Sometimes it works properly, other times it blocks
the software, with the block notice referring to an invalid path like
"C:14Path\App.exe" (the number changes every time) instead of the correct
path of "x:\Path\App.exe" where x is the drive the app is on.

Whenever such an invalid path comes up, WF will invariably block the app,
even if I add an exception for the invalid path. I've been forced to turn
Windows Firewall off because this issue prevents me from using my portable
copy of uTorrent.