Hi,
I just downloaded the v6.7.0 of WindowBuilder, but I can't install it, because it does not find my MyEclipse6.0.1 installation.
I had no problem with v6.6.0, which listed my MyEclipse installation during the install process.
If I "manually" choose the folder where MyEclipse is installed (MyEclipse/eclipse), it does list it, but I'm not sure whether it is the good path or not.