We didn't meet schedule when we worked on new version of Visual Watermark for Windows and postponed some features. One of them was support for old Windows XP. Now Visual Watermark fully support Windows XP API and works really well on it. You can download an update from our website here: Download Visual Watermark
Visual Watermark now works on Windows XP, Vista, 7, 8 and 8.1. Plus, supports Mac OS X Lion, Mountain Lion, Mavericks and Yosemite. Yes, it already works on new version of Mac OS X that will be released next fall.