At the time those dreams were made MB and I were creating dreams for 16.10 resolution widescreen monitors. That was the aspect ratio for widescreen monitors back then. Now, 16.9 aspect ratio monitors have become the norm and 16.10 were fazed out.
The ones you are referring to are encoded at 1792x1120 which for some reason Windows 8 does not seem to support no matter if you have a MPEG2 codec or not. I've found that Windows 8 doesn't like anything over 1080 so 1120 no longer works.
Unless MB re-uploads his at a standard resolution like 1920x1080, they will not work in Windows 8.
For the record, the reason why 1792x1120 resolution was used was that it was the only high resolution that TMPGEnc Express would allow for 16.10. Since that was our encoder of choice, it was the best resolution to use.
I've been working on re-encoding my most popular dreams to work for Windows 8 although I would prefer to stick with MPEG2 due to the higher CPU requirements of AVI and WMV.
As for MPEG2 support, most versions of Windows prior to 8 didn't support it natively anyway. It has always been required to supply your own MPEG2 codec so it makes no sense to me that it's being made out to be a big deal now. Also, MPEG2 was recommended to use over WMV to keep CPU usage to a minimum.
Edit: When I first installed DeskScapes 8 in Windows 7, the dreams encoded at 1792x1120 worked fine. With the version I'm using now on Windows 7, they don't work at all. Looks like I'm going to have to reinstall 3.5 on my Windows 7 machine..