Couldn't help noticing that you have an Intel Mac but are running 10.4.11
Nothing wrong with that but I wondered if the software that came with the mouse was suitable for either of those things.
The Kensington website only shows 4 drivers, 2 for slimblade and 2 for mouseworks and only one of them was anything close to being up to date.
Did you ever contact Kensington, they have free tech support, about the problem.
P
This is a user observation. With much trepidation last week, I say this because I have had problems installing a mouse in the past, I purchased a new Kensington Ci20 Wired Optical mouse after reading all the glowing reports of it on a number of websites. I had numerous problems during installation of a simple MOUSE! The user guides were LESS than instructive nor user friendly! The feel of the thing was satisfactory but it has so many bells and whistles that I will NEVER use it is incredible! Most all conflict with the mouse is this, jerky and sticks constantly on the screen. I have adjusted, deleted everything related from my VERY old MS USB Optical Blue Mouse that I have been using for five years or more with very little problems EVER, uninstalled, re-installed, restarted, repaired permissions, etc., nothing worked! The reason I needed to replace the old mouse is because the plastic case was wearing thin where my fingers have gripped it over the years. I simply needed a new one.
After over four incredibly frustrating hours of trying to make it work easily, including talking to their help line, I finally gave up in disgust and will be returning it for refund this week. I have a fully functional generic optical mouse that came with a Matias USB 2 keyboard that I never used. I unplugged the Kensington, installed the generic and it works very easily on the first try! My mouse preferences in Mac OS 10.4.11 on my Intel iMac work just great, the tracking is smooth and NOT jerky or freezing either. It is a simple optical wheeled mouse with a right- left button and a scroll wheel. Sometimes simple and easy is MUCH better than dixie showboat five button overloaded items with NO instructions what so ever! Some of us were not born with computers on our chests or raised with them. Now I know others may find the Ci20 a great item, and to be fair Kensington produces many fine products, but me today with the Ci20 Optical mouse, naa! I'm staying with my simple one- this one goes back to the store for refund!
Frustrated and disgusted are the best words I can say now. Sorry but this product came very highly rated, but not by me.

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