Current description on https://devstudio.jboss.com/earlyaccess/7.0.0.Beta1.html says:

The Visual Page Editor does not run on 64-bit Windows or Mac. While the source editor does work, visual editing & preview do not. If you require this, run the installer with a 32-bit JDK.

Making readers believe that we do not run on 64-bit OS. The real issue is 64-bit JVMs. A 32-bit JVM on a 64-bit OS is great.

So, a rewording attempt:

The Visual Page Editor does not provide visual editing nor preview when run on a 64-bit JVM. However, it does provide visual editing when used on a 32-bit JVM even on a 64-bit Windows or Mac OS X.