A lot of people don't care if it's in the markup panel or not, myself included; I only supplied that as a request, and quite frankly, I have no idea if it even works as I never tested it.
The other, the spoiler tags in the lib, has been heavily tested.
Donate to UBBDev today to help aid in Operational, Server and Script Maintenance, and Development costs.
Please also see our parent organization VNC Web Services if you're in the need of a new UBB.threads Install or Upgrade, Site/Server Migrations, or Security and Coding Services.