How many variables (Variable 1 [var1]) is the maximum amount I can use?
You can add an unlimited amount of variables. Note! when you use over 150 pages you will get a notification that your system might get slow. WordPress and your server simply can’t handle 1000 pages simultaneously on the server. If they do theres a chance they will bring other users on the server at risk. So watch the server load when creating a high number of landing pages.