I wasn't sure if the () was necessary, but I tried with and without. Without it just throws a null exception. With it says "ERROR: There was a problem applying a Botania Tweaks action.

Found the bug! I was creating the default recipe object after CT scripts executed. The script ended up trying to remove a recipe which hadn't been defined yet, freaked out partway through the logging routine (oddly enough), and throwing a NullPointerException. Fixed it by just creating that recipe object earlier.

Thanks for the report. This will be fixed in the next release on Curseforge, I want to add some more things first though.

I'm glad it wasn't just my lack of scripting knowledge. I'll keep an eye out for the update, thanks!

Update's now live, as 1.3!