I am in Australia. Sent my MMM to Castle in January. From the day I posted it off at the local post office it took 24 days for me to receive a replacment. 24 days is very good considering that at least 7 days of that would have been travel time. Can't complain about Castles service my self. I think do what Neil said and contact them. Who knows, maybe it's been lost in the mail.
The yellow is most likely just flux and yes, both that and the amount of solder is normal. Really, there is no need to have more solder than that; there are no gaps and the bullets look like they are firmly in place.
Right before I sold my Revo I had the exact same issue. It turned out to be the bullet connectors not getting enough contact. I stuck a small wrench in the end of the male bullets and stretched them out, worked like a charm after. Try it, it might work for you too.