you don't say if your compiling enigma or neutrino, I thought the epg fix was now in the cvs for enigma but not sure as not played with enigma for ages.

The easiest way to to make a shared folder in windows then link to the shared folder from ubuntu but a quick fix is to extract with winrar in windows then ftp it to the box then use the ftp in ubuntu to get the extracted files from the box.

There are a few unrar programs for linux you might be better of installing one of those in linux and save the messing about.