Thanks for your reply! Here's some more details:

I already have 3 projectors from another project that I would like to use for this. So I would only need 2 more. That opens up more of the budget for other hardware/software. The projectors I have right now were about $3k each, so they are decent projectors for what they do. They are 1080p and support a whole slew of signals/connections. So I would like to continue with these and not get all new ones unless I have to.

As far as the space... right now, the stage is 25-30 feet wide and I have 12 feet of headroom before hitting stuff. Lighting could be the biggest issue. But the rig can be adjusted as needed to make this work. During scenes when I have to use my front wash, I just accept that the lower part of the screen will get blown out. That isn't when I really need the wall though. This wall will really be used when I'm lighting the stage with out-focused movers with colors and LEDs.

When you say "playback hardware", what exactly do you mean? I still don't quite understand how this works. Is there some sort of hardware unit that will trick the software into thinking it is some kind of screen with a weird resolution when actually it is just taking that signal and distributing it out to make one large screen? I guess that is where I'm most confused.