Hi Michael,
Using the script engine inside Xpression probably won't work because there's no method to capture your keystrokes.
However, there is certainly a way if you us an external application in VB or C# but it does require you to have the AE version of the Xpression software.
There might also be a solution using the CII-gateway, but for that somebody else would have to help you out as I have never used the CII.
Best regards,
Kenneth
#XPression