Dim Dungeon is a custom track made by MK Realm. In the beginning of the track, there are two paths you can take: the left side has item boxes and the right side doesn't, but it has a boost panel instead.
v1.0 has a really heavy slow motion bug. If playing offline, the intro camera and the race are very slow; online and offline. Because of this, Wiimm analyzed the KCL (by »wkclt dump track.szs«) and found 6936 (48%) invalid triangles. So he tried the command »wszst patch --kcl new,drop,small --tri-area 5 --tri-ht 1 track.szs«. After patching, the bug is gone in offline and online modes. The file size is another factor, where it's about half of 1029 KB than what it was beforehand. Because of the experience with this track and others, Wiimm increased the default values of the options.