The spinning clock is not part of your course but a warning from your browser (the program that gets you on to the Internet) that your communication with us is slowing or has stopped. This occurs when there is too much backed up data (history and cache) in your browser.
Please open the history settings in your browser and delete any temporary history and data. You will most likely have to restart the browser before logging back in and continuing from the beginning of whatever set of slides or exam you left off in.
Each browser handles clearing cache differently. In general you can hold the Ctrl and SHIFT keys on your keyboard and tap the DELETE key to open the delete or clear menu.
More detailed instructions for your particular browser is located here:
http://www.refreshyourcache.com/en/home/
Keywords: Stall, clock, wheel, timer, spin, cache, history