VirtualBox not creating VM on openSUSE 13.1

Hello,
I’m running the latest RC of openSUSE 13.1. I want to install a Windows 7 VM, but the VirtualBox wizard will not get past the initial dialog. I click on “New” select an OS version (doesn’t matter which, I get the same error for all of them). Then I use the default name, or change it to another name, then click “add”, and I get the following error:

Could not create the VM
This parameter must be a string or Unicode object

I have no way of knowing if this is related to testing a beta version of openSUSE, as I have never used VirtualBox before.
Any ideas?

Uninstall vboxgtk and use the official VirtualBox GUI (package “virtualbox-qt”).
vboxgtk doesn’t correctly work with recent VirtualBox versions (you can start a VM however), and seems dead anyway.

That works. Thanks!