Hi TM
It sounds like your problem with the validator and the mod trying to find each other may be the problem if the NewUi mod has not been enabled correctly.
Although the mod validator is available as a separate download it comes with the NewUI mod and is found in the data\applications folder along with other applications.
Post #7 TDW's NewUi 7-5-0 Installing It Correctly
Post #28 JSGME Mod Validator Instructions
SHValidator_v_2_0_6_0.zip
Peter