I think it works! (after you remove the extra closing parenthesis at the end of line 1087 of refractainstaller-yad.)
I installed wheezy in vbox with no bootloader. Then booted into the installation using a grub boot cd, installed grub-legacy, ran 'grub-install /dev/sda' and 'update-grub' and was able to boot into it. Did it this way to avoid ever having grub-pc installed and purged.
Installed refractasnapshot-base-9.0.5-4 and refractainstaller-base-9.0.5-3 with dependencies, added the slavino repo and installed yad.
Made a snapshot. Booted the snapshot. Ran refractainstaller-yad, and installed system and bootloader to /dev/sda1.
Rebooted with grub2 rescue iso, went to grub command line and booted by chainloading the grub-legacy bootloader in /dev/sda1. It worked. I got the grub-legacy boot menu, and it booted.