A full no-go with the GoPro Studio Premium. Clips cannot be transcoded, show up black and progress stuck a 0 percent, previously transcoded clips are not controllable (primaries, color etc).
At the same time old version (very old) Neo 5.6 runs just fine.

What sources? This is not true for all cameras.

GoPro Hero 3 Black. In this case of this media the destination folder is filled with chunks 4 Mb each that are corrupt for each attempt to perform conversion

.mts from hacked GH2 are ok.

Previously converted to Cineform avi or mov - no go, cannot be adjusted in the edit page, unless converted to Cineform in the version 2.

the workaround for color adjustment on the existent cineform clips is to change zoom level (e.g. from 1 to 1.001). At that point any adjustment in primary and other groups become visible.If zoom reset to 1, then all of the adjustments become ineffective again.

I had problems with Windows 8.1 and my Sony Content Browser S/W. It is not compatible!

I ended up having to reload Windows 7 on my machine. Windows 8.1 is not a very good product IMHO.

BTW, if you want to get back to Windows 7 and have already loaded 8.1, you can't 'remove' 8.1! Microsoft deleted the 'remove from disk sector' command from the options. It permanently resides in a file called Windows dot Old.

My IT Service and I spent a week trying to understand what was happening and then reloaded MS Windows 7.

It was a nightmare! I also lost a client because I couldn't turn the project around in time!

JMHO, YMMV.

J.