This behavior is very unexpected. We added support for IE10 in build 2012.1.719, which is much earlier than the build you are using. Let's try to eliminate if the problem is specific to your application or your machine.
- Create a new project
- Create a new test
- Start recording
- Navigate to http://helen.org.ua/caramel/ (this is another simple Silverlight application)
- Record a couple of clicks
- Play back the test
Does this work? If yes it proves the problem is specific to your application. We'll need to find a way we can reproduce the problem before we can diagnose the cause. If no, it proves there's still something not right about your computer.
We'll figure out the next step based on your results.
P.S. When you have an urgent problem like this, I recommend filing a support ticket right away instead of starting a forum thread. Forum threads get lower priority than support tickets (72 hour response versus 24 hour response).