Has anyone had any issues with the latest payroll tax update?

SOLVED

Our client upgraded to Sage 100 2019 and Payroll 2.19.4 on December 3. Ran their first payroll and, while some federal tax withholding amounts were different from previous payroll runs, none were outlandishly so. After installing the latest tax update on December 16, client ran a payroll for the last payroll period of the year (12/31/2019 check and period-end date). Federal Withholding amounts on all employees are drastically different from the prior payroll run. Some employees' withholding increased substantially, while others' decreased. In one case, an employee's withholding dropped over $500, even though he voluntarily has over $700 withheld each pay period.

Has anyone else tried to run a payroll after installing the latest tax update? Is the above an indication that there is a problem with the update or with the tax calculation engine? Or, possibly, that the tax update should have been held back until payroll 2.20 is available?

Is there a way to roll back the tax update once it has been installed? The above situation was on a payroll of only 7 employees, so we were able to use Manual Tax entry to correct the withholding. Their next payroll run will cover over 100 employees, so we need it to be right.