[sualfred]

I've jumped off the roof and tested my 1000 movies today. And..... it seems nothing is messed up.

1. Yes
2. Not added yet, but no problem.
3. -> MPAA. This is tricky but doable with tmdb, but reaquires an extended API call with a region (and a region setting in the addon). The question is: Why should this be in the rating updater task? The MPAA doesn't really change over the time.
3. -> Top250: Either TMDb nor OMDb is having this information

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@nessus 

regarding 2) RunScript(script.metadata.editor) will offer you 3 options. And a cancel option if the updating is configured as background task.