Is BLS-2016 compatible with Windows Vista

Yes, BLS-2016 will be fully compatible with Windows Vista.
As a note, Microsoft has ended mainstream support for Windows Vista on 4/10/2012 and has set 4/11/2017 as the end of the extended support period, to which the operating system will become fully non-supported by Microsoft and can no longer be officially supported by CDE Software. As such, we highly recommend upgrading to a newer version of Windows.