There's several ways to play Namco High nowadays! Through Flashpoint, The Unofficial Homestuck Collection, that one Neocities page, and that one Ren'Py port are all the ways I know how to play it post-ShiftyLook shutdown. I'd personally recommend the UHC's version of it, but the Flashpoint version is seemingly closer to the original version that ShiftyLook hosted. Alternatively, you can just use the Ren'Py port if you wanna play a version of NH with Ren'Py's features.