A single screenshot of Photo Mechanic using a lot of CPU is not a lot to go on. Photo Mechanic will use a lot of CPU power at times, as will any almost any application.
Do you have Photo Mechanic set to Restore all Contact Sheets open from the last session? Do you have RAW Rendering enabled in the Render Cache section of Photo Mechanic's Preferences? In the other thread you stated that deleting your cache folder helped in some way, did it make this high CPU usage problem go away?