I have an update. As discussed in https://build.opensuse.org/request/show/697900, the openSUSE maintainer of acpica is unwilling to accept the patch that I tested. He will be waiting for the upstream maintainer to complete all of his tests to verify the patch. Of course, that ignores the fact the the test suite completely missed the introduction of the bug! :) Until those tests are completed, and any fixes are done upstream, booting of Windows 7 VMs will continue to fail UNLESS you follow the prescription of comment 5. If you have Win 7 VMs and the above fails, then please notify me through this bug report.