Problem with keygridconnector

I tried to use keygridconnector and found some problems.

On server-side when i use in render_sql for index in my table two columns name as primary key in my table on the server, i can see all rows from the server, but i can’t insert new rows into table. And when i use only one column for index in render_sql i don’t see all rows but i can isert new rows. Is it a special feature of keygridconnector? Is it resolveable?