Just wondering.. since the normal plugin not developed by WPMU works on single sites..
When activating the plugin developed by you I got this error.
Fatal error: Call to undefined function get_blog_option() in /home/sitename/public_html/wp-content/plugins/whoseesads/whoseesads.php on line 386
The reason I was trying to use this plugin instead of the normal one not edited by you was because the original is bugged. I set the regular visitor to 5 posts per 1 day, and the ad would still show if they viewed 2 visits. When I set it to 25 posts per 1 day it would show the ad at 7 or 8 page views. It appears it was bugged in that it would never be accurate in how many pages were viewed already.