I've got several sets of launchers, one to launch apps, one to open folders in Explorer and another to open websites in a browser. I've re-used the same code across each but the web launcher is opening the page twice. Here is an example of one of the button's code -
Next, open the log (right-click the tray icon, and click "About"). Then click your button while watching the log. If you only see the "Button command sent!" message once per click, then Rainmeter is definitely only sending the command once.
Weird. I used your log code and it was definitely only sending the info once and now it seems to have fixed itself. I think maybe I was refreshing the wrong skin or something before, when I thought I had found the problem. Whatever it was, thanks for the help.