I am not sure when this broke, but we recently installed 5.5 on top of 5.4 in Dev. and I am having the issue below for a 4.7 process in VS2015.
View Code - Destination Event
(!) Method 'DestinationRule_ExecuteCode' could not be resolved. Either method could not be found or method... (cut off)
Cannot right click and use "Generate Handlers" (to put custom code in the Initialized event), gets "Cannot create method in the associated activity 'DestinationRule_6ab3xxxguid'. Make sure a class with this activity name exists.
If I manually try to copy/paste code to manually pasted initialized event, it's not actually being called when destination event runs.