"Given that this is a very early build, please install in a test environment with no earlier versions of Visual Studio installed."
I had a brief moment of panic thinking that this version wouldn't co-exist with others after reading your post. :)
>"Installing a CTP release will place a computer in an unsupported state. For that reason, we recommend only installing CTP releases in a virtual machine, or on a computer that is available for reformatting.
>Currently, Visual Studio "14" CTPs have known compatibility issues with previous releases of Visual Studio and should not be installed side-by-side on the same computer."
I don't know how serious that statement is, or maybe it's just a big blanket clause. But it seems like they really, really think you shouldn't install them together.
That's what I use, you can find the Windows 8.1 Ent Evaluation here
http://technet.microsoft.com/en-us/evalcenter/hh699156.aspx
I think they give you a key by registering for 90 or 180 days to evaluate it and try it out for free. Make a virtual machine in Vitualbox.
I choose Virtualbox because it has a GNU/Linux and OSX version, unlike VirtualPC so you can run virtual machines on GNU/Linux and OSX systems.
Some people like VMWare, others QEMU, and some use what Microsoft has. But Microsoft has these evaluation ISOs for free for a limited time so if one runs out, just reformat and reinstall it in a virtual machine to test it out.
And how does the VS team even get the signing keys to ship a new Windows kernel?