I'm trying to design an application which shows 8 preset window layouts based on turning on or off 3 different switches.  I have been trying to figure out how to simulate this with axure, but I can't figure out how to do it.

 I have 3 buttons for 3 different windows called Video, Comm, and Board.  Each one can be turned on and off, so there are 2x2x2, or 8 possible configurations.  I'd like to be able to press each of three buttons and show a different dynamc panel layout based on which combo of buttons is pressed.  I think I need to set a variable for each one of the buttons, so i can be switched from 1 to 0.  and then i need a dynamic panel to be able to read 3 variables and display one of its 8 panels based on which variables are on or off.  Is this making sense?  Anybody know how I can do that?

If you want this to exist all on the same page, you can accomplish this without variables.

Let's say you have 3 checkboxes for the 3 switches. You can add cases to the OnClick event of each of them to set the dynamic panels states accordingly. The OnClick on each of the checkboxes would contain the same 8 cases with conditions like

"if check state of MyCheck1 is checked and check state of MyCheck2 is not checked and check state of MyCheck3 is checked"

then add the appropriate actions. Here is an article and video on conditional logic: http://www.axure.com/p202_1.aspx

Once you've defined the cases on one of the checkboxes, you can right click on OnClick and Copy All Cases and then right click on OnClick on the next checkbox and paste all the cases.

You can also consider linking to different pages based on the checkboxes to show the content in the different layouts. This could help keep the pages simpler depending on the dynamic panels.

Also, if you don't need to demonstrate all 8 scenarios dynamically, you could consider making just a couple of them work and then use annotations and less dynamic pages to show / describe the rest of the combinations.