I don't know where the .mc file extension came from?
Cinamagraph should make 3 files each picture; .jpg, .mp4.tmh, .nar
Find the date and time of the pic you want... Copy the .mp4.thm to your computer > right click the file > edit the file name by removing the .thm so it ends in .mp4 > click OK > click yes to teh changed file extension warning.
You now have an mp4 that plays in your favorite video player. If you want a single frame, pause the video and use a screen capture tool.