The full error is "UNHANDLED EXCEPTION AT ADDRESS 0000B77A is not an integer value"
This is a known Treatware issue and may be due to the version of POS that you are running.
As of May 2, 2019, the Treatware POS version is 188.8.131.52.502. To confirm that the POS version is correct, there is a version button available at the top of the screen next to the time. Press this button and the correct version will appear.
If the version is incorrect, you will need to contact ICS at 800-826-9480.