Hi Sathish,
one save is enough. If you save and without changes you save again simply nothing should happen. That you get a dump in the latter case is a bug, maybe solved with note 2221817.
That after save the save button will change to inactive is not usual in SAPGUI transactions. I don't know how it is implemented in RSPLAN. But, of course, the system should not dump if there is nothing to save.
Regards,
Gregor