"I then deleted the engine from remote and then went to add new MTH engine. Surprise! The engine was added to address 1. The engine started up and everything is working." I have lost count of how many times I have done the same, sometimes with success, rarely not. DCS also has a "recover engine" function.
Above all, I keep engines (and cars) in plastic containers in as dry an environment as I can. Does anyone else know if this last effort is worthwhile?