Glad to hear - sorry realised I copied the wrong table values (doing it from memory and notes). Be careful with making changes directly in GRFNMW_CONFIGURE - sometimes it's a good idea to go back to the MSMP screens and check all is working. There are a few other GRFNMW_* transactions codes relating to MSMP as well that may come in handy for you.
I don't have access to a GRC system at the moment to check the first two. I suspect the ReqNo verse ReqId is there differenced between Request Number range for the request (what the uses sees) whilst the ReqId is the GUID type number that uniquely identifies the request (refer to it in MSMP instance runtime)
Hopefully someone else in the community can jump in an answer your first two questions.
Cheers
Colleen