Things have stopped working
If CabinetSense just isn't working the way it's supposed to, it could be that the program has encountered an exception that it doesn't know how to handle. Fortunately, it's easy to find out if this is the case. Open the ruby console (Window->Ruby Console) and then retry the activity that you are having trouble with.
Here's what the console will look like when you have encountered a problem:
When this happens, send an email off to support and we'll help you resolve it. It is appreciated if you would send the SketchUp model along with a short explanation of what you were attempting to do when this happened.