Hi Matthijs,
my first guess, because of the parsing error, is to check the version of the android x86 image, is it 4.2 or lower? i used “android-x86-4.4-r2.iso” from http://www.android-x86.org, then only installed the mooshimeter app via browser. the bluetooth usb stick has to be inserted into the host before starting the vm. bluetooth should be switched on if not already on by default.

optional is installing a screen rotating app or cursor movement is difficult with the head rotated 90° :-). i noticed that pressing STRG+F10 or STRG+F12 in the vm switches between text and graph mode, so this function can also be used in the emulator.

i have no experience with virtualbox, i only tested vmware player and read that virtual box should work, but that shouldn’t be the problem here. this might only matter in the way how/if usb devices can be used in the vm.