I've installed the latest Technology Preview under the latest beta of El Capitan but I keep getting the error message "Could not open /dev/vmmon: No such file or directory."
I've tried re-installing without success.
It's a very similar issue we had met, please check your file /sbin/kextload, it's a required system binary for loading kernel extensions.
Any chance you can mirror the dmg for another El Capitan user? Vmware's download link is down