I am ready to start construction of my projector and have the pro lens kit.
Just so that I can go ahead and get most of it done, I was going to use the bad fresnel in the simple projector design (both fresnels behind the lcd) and then pull the bad lens out when the good lens comes in.

Just to confirm.... as I understand it, this design should work with the bad fresnel. yes? No?

It isn't perfect, but it will work well enough.

What can I expect the shortfalls to be (besides no keystoning)? That way I know what to try to correct for and what to let go.

if you build it with the lens in front then you just end up with semi blurry and dim edges, i have mine setup with keystone adjustment and it works good enough to watch movies, it is rather hard to read text online at the edges of my screen when my monitor is setup 1280 by 1024 resolution. I see no reason to build it without keystone, just make it like the lens you have is the right one, it will be good enough to use. This way literally all you have to do is drop in the new lens when it comes, and dont have to readjust your monitor and such, i hate moving mine, too much money to break.