You might want to keep it simple to start. BIAB using RT's into Real Band, record your rhythm guitar parts, mix and export to WAV or MP3. Real Band has everything you need to make a very good sounding backing track.
My only admonition would be to do your final mixing/mastering through the PA system you intend to use live. A mix can sound great through phones or good monitors, but horrible through a PA.

Regards,

Bob