I had a similar problem. I opened the Import dialog, navigated to the folder containing the images to be imported and clicked on "Import All". C1 imported way more images than were in the folder, often grouping them with images I want to import, even giving them the same file name. I had to manually delete those unwanted imports.
Then I made a discovery: When I select all the images I want to import, the command button changes from "Import All" to "Import [##] Images". Clicking on that command imports only the images I want.
Hope this helps.