Subnet HD is in flash. Just as all other HD releases.
All items will have use, as for cipher plates - not necessarily.
Changing subnet from flash to gm would be painfull, but once that goal is met (3k/month) - I would surely do it. But once it goes gm - there's not online version anymore. I'd put it on steam and all future updates would happen there.
I'm not answerijng who is Liz, nor what future games will be about. Sorry