Xailer & OZ Software

I am trying to write a value to a registry using the following code. It
fails to create a registry key.
WITH OBJECT TRegistry():Create()
nError := :OpenKey("SoftwareAlterraCheckPointFiles_Folders")
IF nError != 0
nError := :CreateKey("SoftwareAlterraCheckPointFiles_Folders")
ENDIF
IF nError == 0
:SetString("TVSelection", ::oEditBtnTVSelection:cText)
:CloseKey()
ENDIF
:Destroy()
END
Even if I create the key - using RegEdit - by hand
("SoftwareAlterraCheckPointFiles_FoldersTVSelection") no value is
saved.
Anybody any idea?
Stephan