The other post concerning tool tips is
listed here. It was also an issue with a user using Win 2000. His name was Tom, so I thought it was you posting under a different username.
Tooltips have been completely rewritten, and there are no known issues. Let me know if you have problems using the latest beta, which has a timestamp of Feb 1.
If you do have an issue still, please:
1) Verify that you have the Feb 1 version
2) Select the "Step - New" menu item. Do you have a tool tip from that? it uses the same code
3) Hold your mouse for a second or two over a button inside of the Properties window. do you see a tool tip?

This also uses the exact same code that is run for the Tool Tip action.
I'm fairly certain that the Beta that was uploaded a few minutes ago takes care of the problem for you - faulty code was identified (and corrected) in the tooltip section.