Hi, Dasyar.
BMicro no longer supports the 531x or 801x compilers. It is all Studio, all the way. Studio's latest shipping version supplied in the download section is here:
http://basicmicro.com/ViewPage.aspx?ContentCode=d_basicatomproThis is Studio 1.0.0.14, Beta. You'll find Pro 8.0.1.7 there, too, but it is NOT supported. Studio contains BOTH compilers, Pro and BasicAtom, and these represent the latest bug-fixed versions.
This also applies to the BasicAtom's compilers, 2211 and 5310. They are provided but not supported.
Take care.