"Custom SQL filter is incorrectly formatted."

I believe you're running into two problems here, first, when you click on "Edit" and expand "Show Filter Examples" you will note at the very bottom it says "Show list of Node Properties" and "Show List of Volume Properties", both of which have a "Status" available to them.  So Orion is confused as to which you want to use.

Prior to 11.5.2, you would have gone

Nodes.Status <> 1

or

Volumes.Status <> 1

depending on what you wanted...

But there is no more "Nodes" table, it was replaced by "NodesProperties" and "NodesData", so now it would be:

NodesData.Status <> 1

instead.

You can find this info here:

http://www.solarwinds.com/documentation/en/flarehelp/npm/content/orioncoreagusingnodefilters.htm

Specifically in the "Database Changes" spreadsheet which is found at a link on that page. 

Here is the link to save you a step...

http://www.solarwinds.com/documentation/en/flarehelp/npm/content/resources/databasechanges.xlsx

HTH!

That does it! Thank you!

Sadly, both of the links in the Correct Answer are no longer valid.  If you happen to have updated links, I'd love to follow them!

Don't have and couldn't find the updated links - however following Craig's advice to "edit" - expand "filter examples" - then "show properties" - worked for me.