Program via RFU, yes... though it would be rather limited. You can not access patch or setup via the RFU. The express can not do external midi faders.
With many limitations, yes.
Playback, yes. Program, no. For one, there's no MIDI note or MSC command for "record," which is kind of a deal-breaker when it comes to programming.
You can if you write a macro to access those sections.
Yes. Expression3/Express/Insight3 Off-line Software v3.1.1.zip