The error:

PHP Fatal error:  Maximum execution time of 30 seconds exceeded in gallery/modules/exif/lib/exifer/makers/ on line 81


The reason:

The exif have been updates with Gallery2, but the libery have not been updated.


The solution:

Download the newest file for olympus images here:

Replace the "" with the new file, and everything works.


Source for solution:
Gallery2 forum