It works fine for me, be sure to choose guest mode though.

Virtualbox on a W10 host.

edit: screenshot http://i.imgur.com/Ev7Kvil.png

Works fine on Virtualbox using 'Linux' as Guest. The mouse DOES work, it just doesn't show the cursor, if you click and drag, it will show like a "finger cursor" on screen.

To navigate the menus, you can use tab, as usual. (in the case of the "next" button.

Seems to be working - boots up to language selection (which I believe is a "normal" app), but won't let me choose any - mouse clicks register for language selection, but not for the "next" button, keyboard: nada :( Cursor only updates on LMB held down (with mouse integration and without). I think there's more work to come back to desktop-ish user expectations.

W7, x64, VBox 5.0.2, Windows guest w/ 1 GB RAM

I have it working on a Linux host as a Linux 64 bit guest with 2 GB ram. You have to change the input device from USB tablet to PS/2 mouse in the VM settings.

However, it's very slow and the taskbar is green most of the time. also, there's a test (block) cursor blinking in the middle of the screen.

Configured as Other Linux 64bit w/12gb of disk and 2gb of memory it booted for me in VirtualBox

Nope. I also tried it on a ESXi 5.5 . The only small notification i see is that it cannot determine the USB writing speed and then it reboots again. So perhaps because it doesn't have write access.

Are you running the same architecture? assuming Remix is a 32 bit download.

e.g. I have previously had problems with virtualbox and a 32 bit guest on a 64 bit host (old cpu/chipset combo)

No, same issue here with VMWare player.