this mod, which is specifically made for 1.12.2, says it's only compatible with quark version 1.6-180, but the most recent build of quark made for 1.12.2 is 1.6-179

How can this mod demand a version of another mod that doesn't exist? What do I do?

whoops lol, apparently the version of quark on their git page (r1.6-180) is unreleased :P, fixed in v1.0.1