I installed the 79 beta 2 of RM on a Win 8.1 machine. RM did not crash on startup as it did with beta 1 but the app window (opened fully ) remains mostly occupied by blank space. All the data (folder tree and currently open folder to the right) is located in the upper left quadrant - so bottom half of the screen is just the dark grey background colour and there nothing is nothing but grey background in the right third of the display. This is the appearance without synching RM to the KPA.
This is on Win 8.1 64 with 16 GB RAM and an i7 (haswell) with 1920x1080 FHD 17" laptop screen.