This chains two SWS/S&M - resources actions. 'Add File to Items as Takes' and 'Delete media file slots', think that's what it's called. The purpose of the chain is to insert new media files in items as a new take so that samples can be auditioned alongside one another. The second action is required so that it doesn't insert duplicate takes after the first one of the first file you inserted. I couldn't find a more elegant way to make this work. All my other variations, usually involving the SWS action 'Choose new source file for selected take', didn't work.