Does this software also watermark videos and animate GIFs? All I see listed is using it for pictures.
Yes, the software supports GIF files, but to add watermark to these files, you need the version created for photos. To add watermarks to video files, you need the version for video files. Both can be tested using the official website:
for Photos: http://www.watermark-software.com/products/watermark-software/watermark-software.exe
for Videos: http://www.video-watermark.com/products/video-watermark-pro.exe