Set color tolerance on compare picture

I would suggest using Region checkpoint instead of a picture checkpoint.  You'd first create a baseline image in the Regions of your project (can be done programmatically in both Keywords and Script) and then use the Region checkpoint to compare a picture against that baseline.  This allows for a color tolerance setting.

See https://support.smartbear.com/testcomplete/docs/testing-with/checkpoints/regions/creating.html