I don't know why you might be having that problem, because that isn't the case for me: my screen sets also go over 2 screens, and I've never had any issues, either with this update, or any other;
I haven't noticed any issues either. However, my 2-screen screensets have separate windows on each monitor, so maybe that's the difference?
There have been issues with multiple-monitor screensets in the past, but they fixed them a few versions back.