How can I run an ad-hoc SQL query within TntMPD?

I have 244 gift records that are incorrectly flagged as AvailableOnWeb. I can identify them via the memo.

SELECT * FROM Gift

WHERE [Gift].[Memo] = "not available" AND  [Gift].[AvailableOnWeb] = TRUE;

Instead of manually going through each record in the GUI and unchecking the box, I was hoping to update this using the following update query.

UPDATE Gift SET Gift.AvailableOnWeb = FALSE, Gift.LastEdit = NOW()

WHERE [Gift].[Memo] = "not available" AND  [Gift].[AvailableOnWeb] = TRUE;

However, after saving this query, why does the Run (and Rename, FWIW) button remain disabled?

Update:

"...I can identify them via the *query..."

I didn't want to make Update Queries too easy to run ... safety reasons.  So to run your update query, you have to double-click on its entry in the Queries list to the left.