I have been having a small issue with Windoor (http://www.ozcad.com.au), the magic window and door plug-in from Australia. I had played with the class settings on the doors and windows, and the opening indicators were not being assigned to the class I wanted.
The author of windoor, Julian Carr, told me to use the reset buttton. I have never used this before, but it worked brilliantly, and not all my windoor functionality is restored!
On the dialog box to edit the Pens and Classes, there is a Reset button. This is the button I was instructed to use.
So, if you are having trouble with your windoor classes, try the Reset button.