Hi,
For all LO datasources logic is written in function module MCEX_BW_LO_API.
So just go to SE37 and give this name--if you are an expert in ABAP then debug it else ask some person to get it debugged for you.As it will have lot of includes and module pool so its note going to b easy to debug the same.
Also check this:
Hope this helps.
Regards,
AL