Whether you charge for it or not is up to you. I'm biased, as I may occasionally have uses for something like that and would like to see it open sourced. There are some things to consider:
-If somebody pays for it they will expect professional level support. And I can almost guarantee you will get support requests for things that are outside your responsibility. Just last week I had a customer send me a pc because the windows tcp stack had been corrupted. It had nothing to do with my software or Labview, but they expected me, not their IT dept, to fix the problem. (Which I did.)
-Open sourcing it will probably expose it to more people, providing you with more feedback for improvements.
-You might attract developers who want to contribute to the project.
-Good open source tools strengthen he community as a whole.
-It would put pressure on Rolf to continue improving LuaView.
I appreciate the desire to be compensated for your time, and it's not a bad thing. However, there are lots of people in the Labview community who give tremendous amounts of time with no expectations of monetary gain. Ask Jon Green or Jim Kring how much time they spent on OpenG. Ask Omar how long it took him to do VI Tester. Ask Christian or Ben (or any other champion) how much time they spend on the forums helping people out. I spent a year on the Interface Framework before releasing it to the CR.
I'm not trying to pressure you into releasing it open source, just pointing out that there is an established history of friendly sharing in the LV community. Personally I think the community would get a lot of benefit from an easy-to-use, open source scripting tool.