There is a problem with your PKGBUILD. The build performances set aside. The PKGBUILD [1] provided in the bug report is built much faster. You try to be able to install mkvtoolnix-qt alone without the mkvtoolnix-cli package, right ? Well this cannot work since mkvtoolnix-qt needs the locale/translation. And since mkvtoolnix-cli *must* be a dependency of mkvtoolnix-qt, there is no point to have the manual mkvinfo-gui.1 which is identical to mkvinfo.1. You can if you want create a symbolic link. [1] http://pastebin.com/rtguGrbR
@Benjamin: Feel free to give the diff a spin before we push it, it's working fine here, the only gripe I have with the new GUI is that the left toolbar is completely black, but that may just be because my desktop is powered by GNOME.