look at
http://freearc.org/Research.aspx
it links TWO srep pages, one with stable version (latest 3.2) and one with experimental version (latest 3.93). use 3.93 and check that your installers work
OTOH, you may use 3.2 if you wish. with maximum compression settings it's no different to 3.2 except for faster _compression_
but i don't provide DLLs, so the best approach imho is to use DLLs from trusted sources such as one by Razor