This was a problem for me in R74 and is still a problem in R75. When I open the animation editor, the graphics for the two buttons on the side ("Set origin and image points" and "Set collision polygons") are missing. The buttons still work if you click on them.
On rare occasions the graphics do appear, but in using the system for the past 2-3 weeks I have only actually seen them a handful of times.
Steps to recreate:
1) Create a new project
2) Create a new sprite object
3) Click to place the new sprite automatically opens the animation editor. The button graphics are missing for the buttons on the side.
Workaround: Move mouse in general area of the buttons and the tooltips will help you to locate them. (This is a minor problem for me now that I know where the buttons are, but it would be a bigger problem for a newbie who has no idea where to look and thinks they must be going mad!)
HP Pavilion dv7 notebook
i7-2630QM CPU with built in Intel HD graphics