I forgot to report back.
The problem was that it would work on normal http when installed normally but when you force https logins, it would not work on normal http anymore. So you ether have to use https for the entire site or just forget about ssl logins.
The workaround: install WordPress HTTPS plugin and force exclusively some pages to work with ssl. Then create a login page and put the login script there.
Since I liked the fact it works with buddypress and I was mostly interested in the profile picture and logout function when logged in. I used a wordpress dynamic widgets to make it so that ajax plugin will only show when logged in on every page and will only ask for login information on the secure login page.
Note that the code is kinda in a mess and im not sure if the dev is maintaining it. However I cant find anything else that worked better.