DisappearItems in SAP GUI 7.30: Why doesn't the "DisappearItems" registry work with SAP GUI 730?
(I checked and it works fine with 720 and 710.)

Please create the DisappearItems key under

HKEY_LOCAL_MACHINE\SOFTWARE\SAP\SAPGUI Front\SAP Frontend Server\Administration 
instead of HKCU. 

In 64-bit operating systems use
Frontend Server\Administration

For details please see SAP note 338750.