Hey, i am still having this issue.
I got my main project (which is the game) and it contains a class MapData that i want to import.
There is another project which is for the extension which provides Extension Writer, Importer and Processor.
The Extension Project references the game project because the game project contains the type to be imported/processed.
I have finished my extension project now, and when i add this dll in the content pipeline as reference, neither the processor or the importer is showing up. What is the problem?