I tested a blitz combat, with 3 units attacking a single one, I got a 1/B result. The defending unit was eliminated due to no valid retreat path, and afterwards, the attacker had to eliminate one of the attacking units, thus creating a valid retreat path.
It seems to me that according to the rules, the losses should be applied first, and after all the losses, the retreat or shatter results.
However, with only ONE unit attacking, getting a 1/R result, the attacker had no choice for the lost unit, it got eliminated BEFORE the R result, and the attacker could retreat the defending unit into the hex the attacking unit started in.
Another combat question : it seems that the CW could use shore bombardment from two different (non co-operating) minors in the same land combat. Is it intended ? The way I read the rules, it should not be possible.