The problem comes from the class="input" that you have set for the td elements - it conflicts with RadFormDecorator's styling logic which leads to this error. If you change the id of the class to something else - myinput, input1, etc., you will not experience this problem anymore.
Thank you for bringing this problem to our attention - I logged it in our database and we will fix it for Q2. Your points were updated.
the Telerik team