It's normal to get two icons (not sure about 3) when you launch MC and it is importing files. I believe this would also happen if MC tries to import files and then fails to do so. It would probably try to import them again the next time you start MC.
Once MC is started, you should only see one MC icon in the dock. If you see more than one, then it is likely that you have more than one instance of MC started. Note that the dock icon will have an indication (I think a dot) that tells you if it's running, or if it's just a launch icon. Are both running? Or only one?
This sounds to me a lot like a situation of having started MC from inside the download package instead of dragging the application to the Applications folder.
You might try clearing both from the Dock (with right click > remove from dock), and then starting MC from the Applications folder.
Brian.
