At the bottom of the Lake Sumter web cam is a link to the Spanish Springs web cam, click on that link. Now you will again get the message to install Active-X. Now click on the bar to install Active-X and you should be good to go.
For some reason the install works on the SS cam but not the LSL cam.
In case you cannot get to the SS web cam here is the link but you may need to cut and paste the URL into your browser to make it work.
http://www.thevillages.com/lifestyle/cam_ss.asp