Yes that's right - you need to rename huffyuv_ccesp-patch_0.2.5.dll to huffyuv.dll. Once it's renamed, just right-click on the .inf file and select install. When it's installed, you can delete both the files.
The package at Doom9 includes the source code (which is not required to install) and unfortunately is a little confusing to wok out how to install!