Bob,
This effort to add code to the UserAction is in an effort to work around problems using the Maxim Dual Wheels filter configuration using two, identical, ZWO filter wheels.

If we configure one wheel on the camera (driverID= ASCOM.EFW2.FilterWheel) and the other on the guider (driverID= ASCOM.EFW2_2.FilterWheel) things function okay. The wheels follow instructions. But when the wheels are both selected in a Dual Wheel configuration then the wheel action is erratic; I'm still trying to nail down what is happening.

In our phone conversation you mentioned that this setup was going to run into a limitation of the ASCOM protocol which was not designed to have multiple instances of the same device. Can you explain in more detail?

The other possibility is that Maxim is picking up the same driverID for both of the 2 wheels in the Dual Wheel configuration; it's not clear from the setup information which driver's it is picking up. (that is, when selecting the 2 wheels it is not offering the Chooser).

Thanks,
George