When you make a change to the Menta file and save that file back into Vista the changes are not available in Vista.
An alarm appears stating ( "Object does already exist " when expanding file in database)
In some earlier versions of Vista, illegal characters were allowed to be entered in the Menta program specification name.
Here is a link to describing more on that problem.
Rename the Menta program specification name. No more than 12 character and no spaces or illegal characters. Refer to the following article for illegal characters which can not be used.
Then generate the OP tree for the Menta application and save into the Vista database.