Horst wrote:tanks may tanks shock on. if stopped, they count as destroyed.
infantry may not move on and count as destroyed.
Not actually true.
Tanks can tank shock on. The rules don't cover what happens to them if they are stopped while not completely on the table.
Skimmers and other units that can move over enemy models would have no impediment.
Other models (depending on your viewpoint) either
(1)can't move on... in which case they are only destroyed if the game is being played to a time limit, as there is no way given by the rules to continue from that point, as you have a compulsory action that must be completed before you can do anything else... but that you are unable to complete. So in an untimed game, you're simply stuck unable to continue the game.
or
(2)the requirement for them to move on over-rides the general movement rule forbidding them from moving within 1" of enemy models, in which case they move on through any spaces between the enemy. If there are no spaces between the enemy models, you're back to option (1).
Either way, you'll need to discuss a house rule before the game begins.
TL : DR - The rules don't cover it. You'll need a house rule.