Changelog: https://github.com/SamVanheer/HL_Tools/wiki/Half-Life-Model-Viewer#v211
Note: this release contains wxWidgets binaries that will not overwrite the older ones. Manually remove the old binaries from your installation if you do not want them to take up space.
You should remove the old fmod.dll from any existing installation since it is no longer used.
You will need to install the VS 2017 x86 redistributable, this is included in the archive in the redist directory. If you are on Windows XP make sure to uninstall Visual C++ redistributables newer than file version 14.27.29114.0 because these will break any programs made with VS 2015, 2017 and 2019.
This is likely the last update for Half-Life Model Viewer. You should switch to Half-Life Asset Manager if possible.