The beta 2.05 version is an excellent update and works very well, thank you! However, there are 3 small bugs:
When using a backplate image and region render, the backplate image changes to the size of the region when it should remain the size of the viewport.
The exposure of the backplate should always keep its original exposure and not change when the exposure (EV) is changed - the best scenario would be if this could be an on/off option.
If you copy (instanced) the environment map to the material editor, and then copy (instanced) the bottom map (Lighting:) to a spare slot, it copies the Background (backplate) image instead.
Hey, thanks for reporting these problems.
The easiest fix of these is for the problem with copying/instancing. This was a problem I encountered some time ago with materials and at that time I forgot to apply the fix to the Cycles texmaps. I should be able to get this fixed very quickly.
The other two I can definitely fix, but it will take a bit more time. I'll have to poke at Max a bit to see exactly how I'm going to fix it. I'll post an update in this thread in a few days once I have that figured out.
I've had a look into this and it seems like both of those issues will be pretty easy to fix. I expect to have a fixed version ready within a week.
Quick update on this:
I have this sorted now and backplates will now play nice with both region rendering and the "Process Background and Environment Maps" checkbox. Note that this checkbox will only work for backplates at the moment, not normal environment maps.
I've also found a couple unrelated bugs while I was fixing what you reported here. I'm now working to fix those and should have a maintenance release ready in just a couple more days.
I've just released Beta 2.06 which contains a fix for all three of these bugs. Please give it a try and let me know if you are still seeing any of these problems.