Thanks! All fixed now.
However, I installed it with Maxthon still running, and told it to reboot the browser now. Maxthon closed, but didn't reopen. Tried to launch it again numerous times but nothing happened. Restarted Windows and tried to launch, and got an error that the side by side configuration was wrong and it couldn't run. So had to run the installer a second time, and then Maxthon opened successfully.