Ah i dont understand your post !
an activeX dtPicker seems very simple to use in similar case.

if your control is not an olecontrol one (pure vfp control) you can superpose dynamically an image (capture the image control and inverse colors for ex to simulate it as disabled).
then with this image property visible and !visible to make similar appearance as enabled/disabled. (playing also with zorder(0) to mask the control).
note: olecontrol is always on top and cannot hide it with any vfp control.

the image captured must be exact dimensions of the control.
the image can be created at runtime and destroyed or hidden. (addObject,removeObject )
-(this technic is currently used for checkboxes for ex.)