I have already answered your question in the support ticket that you have opened. For your convenience, I give you the information here as well:
I am not quite sure how you have implemented the minimize/maximize behavior and that is why, I cannot tell you what exactly is causing the described problem. Basically, the elements of the rotator use position style setting, different from "static". This could be causing a problem, in case you have not handled this case correctly in your implementation. In case you send me a simple page, that demonstrates the problem with your code, when used with elements in rotator items, I will do my best to help you fix it.
the Telerik team