That's correct, you should separate each of the solution packs into their own subdirectories to keep the include files intact for each of them. Its up to you if you want to put one of the solutions at the root or not. Its really a decision that you would have to make on how you want the site to be structured. As Neilo said, if you are setting up several sites on the same server, you might want to organize each of the sites by putting them in different subdirectories.