Hi, yes, Forge is amazing, due to a collective fan effort

I'm not sure about
Tawnos, Urza's Apprentice, might it be simply an order of events thing?
As I read it, you need to activate or have an artifact (you control) trigger and let that resolving effect sit on the stack, and it shouldn't be "auto yielded", then activate
Tawnos and chose which effect on the stack to target?
Worst Fears reads like it may require some serious change inside Forge, basically pausing the AI, allow a dev mode like situation (view all cards), then be able to control AND play the opponents resources, which may require additional steps to simply be able to chose and tap a land on the other side and at end of turn give back control to the Ai?
Yeah.. I'm no dev, but I don't see that happening anytime soon
There are only 110(!) unsupported cards, out of 19794 (with individual card rulings), which are too difficult to implement, yet. (Taken from DistinctStats.txt, right under the 1st release post in the release thread)
Everyone is welcome to try their best with card scripting, though
But some are just not happening, maybe ever, without a complete rewrite of the software
Have Fun!
K.