The “Edit Charge Amount” allows you to quickly adjust either the elapsed time or the hourly rate of one or more selected time records given a charge amount.  Select Charge… from the Edit menu to edit the charge amount.

For example, in the figure below the highlighted time record shows the hourly rate is $110, and the elapsed time is 4 hours for a total charge of $440.

Even though the job took 4 hours, you have a minimum fee of $500.  Select the time record you want to adjust, select Charge… from the Edit menu, enter 500, and click OK.  The elapsed time is adjusted to 4:33 hours.  Notice that the charge is adjusted to $500.50.  That's as close as TimeSlice can get to $500 given the values it has to work with.

However, if you wanted to keep the elapsed time at 4 hours and adjust the hourly rate instead, click on the “Adjust hourly rate” button, and click OK.

The hourly rate is then adjusted so that the hourly rate multiplied by the elapsed time equals $500.
Remember that this will override the default hourly rate associated with the job.  If you later change the job for this time record, the hourly rate will not change.  To reset the hourly rate back to the default hourly rate associated with the job, enter minus one (-1) as the hourly rate, using either In-line Editing or the Edit Time Record window.