
You'll get lots of help here. Just ask the questions. As for Mac and add-ons you will have to ask people who use them.
EDIT - I see Rod already answered your question.
I use windows and adding scripts and plugins are fairly simple once you get the hang of it.
Some actually go as far as writing their own code to use with gimp or (G'MIC which is a plugin). I am no where near that clever.
Although if you have got one of the latest gimps it should already have G'MIC with it.
Anyway enjoy your time here and hope to see some stuff from you soon.
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