but why use ent_for_name ? cant you just assign the action to the model, then my would be equal to that model so you would have:

action Door()
{
var a;
for ( a = 0; a < 300; a++ )
{
my.y -= 0.4;
}
wait(1);
}

this is for a door that moves down? the problem with the above code would be that the door would move up as soon as the level is started