Ok... I'll test my mind reading skills!
You downloaded and are installing 'OS9 for unsupported eMac' on your Mac Plus that you found in the attic. You also have a blutooth 12 button super rollerball mouse/ foot controller that worked fine on your Atari ST but it's freezing when you try using it for your install... How'd I do?
I know...I need to work on it!
Hey there paulsmith7! Welcome aboard! There are a lot of knowledgeable OS9 peeps around these parts that would be more than happy to help out but I'd bet it would make it a lot easier if you provided some detailed info on your install like... What OS 9 version? What mouse? What computer?