I am on 10.9.5 and cannot reproduce this error. If you don't mind answering:
Does it only happen when the media viewer is borderless, taking up the whole screen, or can it happen when the media viewer looks like any other window? You should be able to switch between the two types by pressing 'f'.
Does pressing the arrow keys at the top of the manage tags dialog cause a crash? If you open up the manage tags dialog but do not change any tags, just pressing cancel, can that cause a crash?
If you have any local ratings services and can open the manage ratings dialog on fullscreen, does that cause any crashes? In the same way, if you select start slideshow->custom interval from the right-click menu, which should open a little dialog to enter a number, does that crash?