I guess they could disable importing of plugs for the free version. But that opens up a whole other can of worms.
That's the worst thing they could do, it's like you can buy a new car but can't get new wheels for it.
Whatever devs decide to do i just hope it's not gonna be like with Unity Pro and free version. I was so dissapointed when my Pro time expired and realize that things i did are no longer available. They took my game away <img src="smileys/smiley19.gif" border="0" align="middle" />.
Anyway i'm still a bit curious about what will free version have to offer. but C2 is looking so good, even now in early releases so probably will get full version. It's just worth it.