[OT] oddball enrivonment questions

Soliciting some suggestions from the list ubermensch/intelligentsia:

Information:
1) Running a scenario at ECC - low-G, no-atmosphere asteroid. FMAS.
1"/2m. 
2) All combatants will be wearing powered combat armour (Battle Dress).
Fast, with enhanced strength and sensors. 

Queries:
1) Effects of (both hand and rifle) grenades in low-G, Zero Atm. (both
frag and explosive). Do they work? Can you generate a concussion wave?
Are fragments likely to be dangerous further away? Are characters going
to be blown over/around (suppression) by any explosive force? Can people
throw further? How will this affect bounces? How will it
affect accuracy?

2) Effects of low-G, no-atmosphere on: 

Gauss Rifle/Gauss Pistol/Gauss SAW

Laser Rifle/Carbine

Tac Missile Launcher (GMS/P)

Plasma Gun (Man-portable)

3) Effects of environment on movement - faster, slower, easier, more
treacherous? 

4) Effects of environment on wound resolution (if any) - automatic
sealing is present, but is there still an increased chance of an
over-large puncture causing death? How would you change things? Wounds
more severe? Or not?