RPTools are free for use. Any use.
Our only request is that you use and enjoy the tools, and encourage you to be a participant in the community forums.
We love feedback and (ack!) bug reports so that we can make the tools better. In fact, the tools are community driven, so no feedback, no development.
However, if you feel inclined to show thanks you are welcome to. Here are a couple ways:
Or if you want to thank a specific developer: