I removed the default gateways since they will only ask you to upgrade to SC:R. The only gateway currently included with this is iccup. This means that StarEdit and all of the blizzard maps will remain from the 1.16.1 version, so let me know if you think there is a benefit to including blizzard maps for other versions and I can add them in to a separate map directory or something. When installing or patching to a different version, it currently only changes starcraft.exe, patch_rt.mpq and related binaries. The installation also includes WMode.dll for windowed mode plugins and SFNoCD.dll to play pre-1.15.2 versions. This makes a full 1.16.1 installation, including StarCraft.mpq and BroodWar.mpq.
It's primary use is to create a full 1.16.1 installation, but it can also install/patch to any pre-1.17 version or reset the registry to point to an existing SC installation. To remedy this (and since SD SC is apparently now free), I present the Starcraft Classic Installer. During Mod Nights it has become common for people to not be able to easily switch to various SC versions, or to not even have a pre-SC:R installation at all.