Personally, I don't think a MMORPG for The Way will be successful. Mainly due to a few things:
- There is not enough interest, thus, only a few people will play it
- There are not enough people to continually add content into the MMORPG
- The fact that it's in 2D will turn potential players away
I do also have my doubts on Game Maker's capability to handle the enourmous amount of network traffic and processing that is needed to run an MMORPG. It just doesn't seem to be cut out for large scale network applications. Sure, it might be able to handle a dozen or so clients, but what if you have have a hundred or so clients? Even a few dozen clients would be problematic. For an MMORPG, I would suggest switching to an actual programming language, at least for the server. It's less important for the client, since it only needs to handle the communication between itself and the server.
Good luck though. Go and prove me wrong.