Rollovers using Adobe ImageReady

Greetings,
I just started using ImageReady and I'm having problems.
I successfully created the default buttons and the over state buttons, but when I tested the rollovers there are problems.  When you hover over the default state it changes to the on state but other buttons simultaneously change with it.  Can some one please look at it and tell me what I'm doing wrong.  I think I'm leaving a step out.  Thanks for your feedback

Here's a link to the file. It's still in a layers state.
 
http://kip.kennesaw.edu/kedomwonyi/proj3heading.psd

File was created in Adobe ImageReady.

Here are the beginning steps that I took

1.  I created a new layer.  I used the slice tool and chose a particular selection for the first default button.  I chose create selection from this slice and filled it with gray back.  The them typed white text on top of default button.

2.  For the over state I created a new layer - then created an overstate.  Again used the slice tool and created a selection from slice.  I filled the selection this time with black.  Again typed white text.  

Rollovers work but too many overstates appear.