I need to collect some data, calculate a checksum on the data, then send the data & the result of the checksum to the instrument to see if the instrument gets the same result. Could WinWedge be used in this example?

The Wedge by itself does not have the ability to calculate checksums however if you were to use it in conjunction with Excel, Visual Basic or some other program that has a macro language, you could use the macro language in the other program to calculate the checksums. You would be using the Wedge as the vehicle for sending and receiving the serial data.