Hi Jerry --

Through ASCOM there is no such thing as a "unidirectional" or "bidirectional" control. Apps that talk to the wheel via ASCOM can't control this. However the ZWO filter/camera software/firmware may itself have a setting for this. The other angle on this is that cameras (and their filters) often come with both a "native" interface and an ASCOM interface. This is an area where ASCOM has mot been as successful as for other devices, usually because the "native" interface supports features like high frame rate video-like imaging.

With that background I'm going to guess that MaxIm is giving you that uni-bi-directional control via the native driver. Also, for an ASCOM driver, the device specific settings will be stored in the Profile Explorer. I'm guessing that the uni-bi selection is in the camera/filter's settings accessible through the Properties... button on the chooser.

This is a load of guesswork because I'm unsure what "flats moving mott..." means nor "not being too accurate" means with regard to a filter wheel. In any case I think you need to look at the ZWO info and the setup screens for that camera/filter.