I got this to work by providing a date cell value in this format: YYYY-MM-DD
MODIFY TENTECH-1 @CellValue(ROW-COUNT,3,INPUT-DATE)
Then I use the @CellFmtString property with this format: MM/dd/yyyy
MODIFY TENTECH-1 @CellFmtString(ROW-COUNT,3,"MM/dd/yyyy")
This displays and sorts the date correctly.