Hi Karsten - your existing script there should work ok if you prepick your objects, that means to select your objects before you run your script.

If you want to also support post-pick, where it will let you pick objects after the command is started if nothing was selected, then you need to also set up some .htm UI that has a "Done" and "Cancel" button on it. This is because when you right-click to finish selecting objects in the object picker, the rules that the right-click mechanism follows is that if there is a "Done" button it's the same as clicking the "Done" button. If no "Done" button exists, it looks for a "Cancel" button and triggers that. If neither of those UI elements exist, it will then do a cancel which is what is probably triggering for you.

- Michael