The d3drm.dll is the d3drm.dll. It doesn't matter where it comes from, DBC will be able to use it.
(DBC being an 'older' language means that Windows have dropped support for the Direct 3D Retained Mode. The d3drm.dll won't be modified/updated any more, hence I think that wherever you took it from it'll be the latest and final version.)
Just rememeber - if you don't want to fiddle with your system folders in Windows, you can simply place the dll with the DB.exe file (C:\Program Files\Dark Basic Software\DarkBasic" if you used the default install path) or place a copy in the smae folder as any exe created with DBC.
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