Hi Ajay,
Hope you have your field/column added to the visible fields with in config ?
I do not see any issue in your tags. Just change the selection Mode and try it once.
I had made it possible with the simple tag I had given in this thread.
http://scn.sap.com/thread/3390635
Not sure what additional property in your tag is preventing from putting it to edit mode.
<chtmlb:configTable displayMode = "FALSE"
allRowsEditable = "TRUE"
usage = "EDITLIST"
id = "ConfTable"
table = "//YourCNName/Table"
xml = "<%= controller->configuration_descr->get_config_data( ) %>" />
Just keep adding each property and check what is making it behave like that and let us know.
Regards
Vinod