Saving filters like custom actions

[ohrenkino]

@sheepdisease

It's really annoying trying to find these files manually.

You can create a Tool (File>Options>Tools) that opens the windows explorer with these parameters:
'/e,"'$getEnv('MP3TAGAPPDATA')'"'
This opens the Windows Explorer in the MP3tag data folder.
Saving the configuration is performed with the function File>Save Configuration ...

On filters and them being saved, see e.g. this thread from 2011:

Labels or Descriptions for Filter Expressions

No, currently not. But, as a workaround you could create at a place of convenience in your file system a plain text file into which you copy the filter expression and add an explaining text. In case you need a seldomly used filter expression you could consult your text file and copy&paste it back to the filter entry box in mp3tag.