Photo Mechanic won't launch. This is the first time it's exhibited this behaviour. Thanks for your help!
Copy and paste from the crash log:
Command: Photo Mechanic (/Applications/Photo Mechanic.app/Contents/MacOS/Photo Mechanic)
PID: 490
Thread: Unknown
Link (dyld) error:
dyld: /Applications/Photo Mechanic.app/Contents/MacOS/Photo Mechanic version mismatch for library: /usr/lib/libxml2.2.dylib (compatibility version of user: 9.0.0 greater than library's version: 8.0.0)