Win7 cursor slowdown

We have a program that allows opengl rendered objects to be moved dynamically by selecting them with a LMouseuttonDown message and tying the object position to the current mouse position.

In the past this function as worked fine, but is verty sluggish on Win7 machines.

One thing I noticed is that on working platforms, the cursor is the solely the program defined bitmap and the opengl model moves smoothly

On Win7 platforms, the Desktoop hourglass or spinning blue annulous appears and disappears. alternatively with our opengl object.

Its is like both windowns and ouprogran are battleing for sho is displaying which object.

any ideas or how does on disable the windows cursor