During the introduction of BVMS 10.0 the BVMS Plus unmanaged site expansion licenses were not introduced, even though this functionality was announced to be available.
The LIF file attached to this article (in the zip archive) can be imported in BVMS Plus 10.0 installations using the license manager (the license manager can be found in the "Tools" menu of the BVMS Configuration Client). Once imported, the purchased licenses (MBV-XSITEPLU-100) can be activated