This KB describes the reason for the "Could not get mounted hot folder" warning when overprint charts with the Color Pilot.
Start the Color Pilot.
Click the New Proofer Profile button.
Select a proofer.
Click the Proof Chart button.
Add the user everyone with full permissions to the "ProofFolder" share of the proof server system (or create the share in case it's missing), in case you get the "Could not get mounted hot folder" warning.
Verify the permissions of the everyone user and make sure that Full Control option is enabled in case you get the "Could not create profiling charts" warning.