That's right. I have experienced that too.
Turn off that module and use the original DJ Mega Menu.
Put that in Casseopeia position menu.
The main menu then appears in full view.
And when you go to mobile view, the hamburger menu appears. And in Casseopeia it won't go away.
If I switch to the VABS template, I set DJ Mega Menu to the Menu-L position of the VABS template, then I see the main menu in the full view.
But in the mobile view, the hamburger menu appears on the right for a very short time. And then it disappears.
I left the settings as described above.
Can you now see what I mean on the site?
Regards,
Wouter