I have custom input component with poup windows (divs) which open on clicking on a button. While rendering this custom component Radzen renders all html of the component including hidden divs where as it should show only input initially and should show popup only on clicking of button, the component works perfectly in web browser when used in page.
Not sure I understand what you are reporting. Can you post a screenshot or any other additional information? Is it something in the designer or runtime?