Using Regex extraction with AutoCat

Checks I write come into the Description column in the Transactions tab like this:

Check #xxxx: Sh Draft

Where xxxx is a four-digit number. I periodically write checks for the same amount to various payees, so I’d like to use Autocat to append the payee name in the Description based on the check amount, like this:

Check #xxxx: Sh Draft Jane Doe

I tried creating a regex rule with an entry in the Description Regex column:

Check #(\d+): Sh Draft

I put the correct amount in the Amount Min and Amount Max columns, and in the Description column I entered:

Check #$1: Jane Doe

I ended up with exactly the text I put in the Description column, with no substitution for $1.

I’m not surprised that it didn’t work, but it sure would be nice if if did!