The new easy-to-use installer is now part of Webconverger mini by default and out of beta. After downloading the latest mini (>= 3.4) ISO, burning it to a CD and booting your PC with it you should see a boot menu to install Webconverger to your disk. (By default Webconverger is a safe Live CD that will not touch the existing contents of your disk.)
Sooner than later you will be simply prompted to confirm whether or not to replace the contents of your disk:
Installation is actually quite fast:
Perhaps in a couple of minutes you should finally see:
Now you're ready to take out the CD ISO and start installing Webconverger on the next PC.