From what I read on the french forum by people that played the demo . Here is some difference that I saw from 40k
-the model can shoot and move, move and shoot, or run and not shoot.
-The distance has impact on what you need to hit.
-It looks like there is less roll, probably one roll to hit after that if the strength is higer than the resistance the model take a wound
-You can disengage from close combat to try to shoot and comeback in contact.
-Like in 40k it is the unit that shoot. but not every model from a unit have to shoot at the same target. I think they shoot by type of weapon so the heavy weapon shoot at vehicle while smaller gun shoot at troops
-You measure range from the leader of the unit
-there is an activation sequence
There is difference between faction and some people have rumored about 4 factions of human.