Hello oGaga! ^_^
Nitro+CHiRAL has a new version of Lamento out, that they remade to work in Windows 10 explicitly. The older version of Lamento was meant for Windows XP/Windows 7 and (might) have issues running in Windows 10. Because Togainu no Chi has issues in Windows 8/10 (as it was built for Windows XP specifically), they re-coded the game to work in Windows 10. They did the same thing with Lamento.
Because of that, the game uses a different packing format for their script files. So the old English nss-patch.npa won't work on the new Lamento program, so a special "Windows 10" version was released for that. ^^
If you downloaded the game without buying their new version from their website, use the old patch instead. The new one is purely for people who have bought the new "Windows 10" version.