ST Support. Everybody is in the same boat as you, so you are not alone. Harmony hub can control most ST devices that I have but not the other way around unless ST support helps you out. Do take into consideration that this integration is still in the labs and is being worked upon.
As far as I know even if they fix it on a user by user basis, reopening the Harmony Connect SmartApp will re-break itself.
Here is some more information on this issue.