Hello Mike,
This may be a little too late of a response, but I will try anyways hoping this may help others with similar issues.
The "Uninitialized tag" error normally implies that we are trying to read/write a tag which either doesn't exist or is invalid. You can verify that it exists and is valid by opening the SCF file in the TCE, and checking true the 'Online tag verification' menu option from the Edit menu.
If there's a problem with the tag(s), a "stop" sign appears next to them. You can then edit the tag and look at the Connections tab as to why? Usually you will notice that the item the tag is referring to is not present. In which case you will want to make sure the OPC Server does have this exact item.
Hope this gives a starting p
oint for troubleshooting this.
Regards,
Khalid