Another thing to be sure not to miss once you get it is the page http://www.clipstudio.net/en/dl/materials/
You can download literally dozens of free brushes here that have been officially made and provided to users!
http://www.clipstudio.net/en/dl also has samples and various other things, some of which are for use only with EX, and others of which any version can use.
It took me months before I noticed the Materials page, so I hope you'll take advantage of it sooner!
Although I don't use all of the brushes there, I use several frequently, and they are very good brushes. They save so much time with work that would otherwise be tedious drudgery.