Return flight home on Sunday, Jan 29. *G (UA 1K) flying on “M” fare on (Cityline) LH 2366 (CRJ 900), MUC-ZRH, connecting to UA 53, ZRH-IAD in Polaris (Biz). Carryon luggage only, one rollaboard which meets size requirement and one small duffel bag, B&R Cabin Duffel.

1. Would I be allowed to take both luggage pieces on Board?
2. If not, does LH gate check bags and return them to the jetway at the end of the flight, without having to go to baggage claim?
3. Or, would LH just allow me to check the rollaboard to ZRH where I could collect it and then take it to my United flight to IAD where I can take it onboard?
4. What would be the chance of being comp upgraded on LH 2366?

edit: ticket would be purchased on United website.