Hi Prasanth,
This application parameter "SAP-CONFIG-MODE = X"is used for end user personalization of your FPM screen. But for that you need to have special developer authorization S_DEVELOP and S_WDR_P13N.
Please find below link which help you to guide in personalization
http://help.sap.com/saphelp_nw70ehp2/helpdata/en/47/bbbeac2b07296fe10000000a42189b/content.htm
http://help.sap.com/saphelp_nw04s/helpdata/en/fd/2da442dc030e31e10000000a1550b0/content.htm
Thanks
Praveen Gupta