Screen Error using GetMouse when making study larger

I have been adapting an attention task I recieved to use mouse clicks instead of key strokes as input. I have the experiment working when it is reduceded to the 600x800 pixels, which I arbitrarily set to make debugging faster. Now when I expand it to the original 1650x1080 which i need for validity, the study freezes whenever I click. It didn't and still doesnt freeze when smaller. I have updated graphics drivers, disconnected to the mirror monitor, and it is running an i5 @ 3.2Ghz all with the same error continuing to pop up. I don't think it is a hardware issue, and can't fiure out anymore software issues for the life of me. Please give me more ideas to try! Thanks!!!!!!

[Walter Roberson]

You will probably need to use the psychtoolbox discussion board for this, as it deals with problems with the functions provided by psychtoolbox.