If the button works for some functions, it should work for others unless they are in hidden mode still. You would think the controller for this device would not be selective as to what to fail...It should all work or none at all unless they are still configured for hidden mode. I gut feeling is that there is nothing functionally wrong with the cluster and that you just have to try the sequence of events again to reset it back to normal.
Here is a picture of someone that placed some of the info on the odometer screen in hidden mode:
http://i7.ebayimg.com/02/i/000/e7/b5/f95b_12.JPG
(I don't know why anyone would want to do that on an Insight

)
Try this with the car in neutral (if running - ignition on) :
The FCD display has a <=======> symbol displayed to indicate a seqment.
If in that mode get out of that mode by pressing the FCD button quickly then:
Use the FCD button to get you to the odometer reading (and lifetime display). Press the trip button down once and release quickly (this should be trip a).
Press and hold the FCD button for a little over 3 seconds
This should reset trip A info and should look like this afterwards:
http://www.solarvan.co.uk/insight/109mpg.jpg
Do the same steps for trip b and the odometer (if needed)
JoeCVT = Just your average CVT owner