A few months ago I did a MileagePlus redemption KRK-MUC-ROM-CAI on LH and MS. Tickets were issued and was able to fly the first two sectors on LH. Arrived in Rome and was told that i didn't have a booking on Egyptair. Ended up having to fork out €600 in cash to buy the last leg of the ticket to get to my Final destination. Wasn't happy and got no compensation or refund from UA except the points refunded for the original ticket.