I have never played this game nor heard of it, but a few things are true for pretty much every game.

If it plays in full screen mode you will need something to force or fake windowed mode. After it is windowed your next hurdle is limitations in the game, for example does it run gameguard? If so you will have to run on multiple computers as that normally prevents keys from being sent to more than one window at a time. Circumventing or discussing methods to circumvent this limitation can be a violation of the ToS or EULA for the game and would be against the rules of the forum.
Other limitations include focus window checks, the game will only be responsive if it has focus, this can be worked with, but may require a bit of messing with settings in both the game and multiplexing software. If it's a flash game this is probably the case, and you would have to find the setting in the software you use to send to background windows. I know HKN can do this and Keyclone should be able to as well.

It is not necessarily a direct translation of issues, but you may want to look into discussion about multiboxing Lord of the Rings Online, as it has some of the same issues you mentioned and people are able to work with it even boxing on a single machine.

I hope that helps or at least gets you to a place that can provide helpful information.