Dear Pierre,
I have the same problem. ( v.1.66 MAC)
While choosing image files for watermark, files in GIF format can not be selected.

- cannot choose GIF file for watermark
- 螢幕快照 2015-01-25 上午12.25.32.png (12.04 KiB) Viewed 1638 times
I don't know if this is a special case for my MAC.
I would like to add GIF watermark without background color.
Thank for your help and your nice softwares.
LiuPh