Watermarks removal tool can remove visible watermarks (for example, transparent labels) from image using watermarks template. There is command line support.

1. You made watermark on your image using template.
2. You lost original image
3. You can take your template and watermarked image and retrieve original image using my program.

So, in that case there are no problems with template.
Some non freeware program gives watermarked image, and you want to remove watermarks to evaluate program more precisely :) So, you should give to that program big white or black image and after processing you will have a template.

My program does not take off your responsibility to buy that program. If you will continue to use not registered program for any purpose other than evaluation it is only your responsibility.