The problem with stating it runs on a out of date OS is that you are implying that you are going to keep it running on that version in the future. If there is massive security update to Windows 10 that requires a re-write of portions of the code, then you would have to make changes for Windows 10 and put in a sub-part of the older versions to keep it running as you promised it would. However if you say that Windows 10 is the minimum and it happens to run in a prior version then you got lucky.

Poser 5, 6, 7, 8, Poser Pro 9 (2012), 10 (2014), 11, 12, 13