Hi Rakesh,
With example mentioned above, I dont understand that why your requirement is not getting fulfilled with standard system.
If you want to post first and last condition then you can select CO01 in condition type selection and RO1 in Rental Object selection.
In this way you would be able to post first condition only.Then if you follow the same way for CO01 and RO2, your last condition will be posted.
Please elaborate a little if its not fulfilling your case.
Regards,
Sid