I lost several hours on undocumented aspects of the beta installation.
It is possible to select C++ while deselecting TBB. This will cause the C++ (and possibly Fortran et al.) to fail.
There is no support for MIC KNC in the beta (even for linux), although KNL is supported.
On both Windows 8.1 and 10, Software Assistant failed at the end of installation, but this seems to be associated with missing documentation and doesn't affect usage otherwise.