Mac OS X 10.9, AMD 5870
Broken: 2.71 official
Short description of error
2.71 added a convenience function to the node editor to auto-load image sequences. However, this function won't work unless the sequence starts at frame 1. If it starts at some other frame number, say, 60, the function will just give an error. It would be expected to load the sequence and adjust the start frame (or maybe the offset?) to compensate.
Exact steps for others to reproduce the error
-Get an image sequence that starts at some frame after 1. For example, set Blender's start frame to something > 1 and end frame a few frames higher, and hit "render animation".
-In Cycles or the Compositor node editors, use the import image sequence function and select the first available frame in the sequence. You will get an error that frame 1 couldn't be found, and no image will load.