Same here Ubuntu 14.04.03 LTS via Wine 1.7.44 the bug present even in Wine emulator within "playonlinux" scripted installation. So you just confirm to me that my linux setup was OK and I'll didn't do nothing wrong. These bug appears even in my wine which is Windows XP by default + some libraries installed and winetricks to support League client. With intel cpu microcode, oem intel hda alsa drivers dkms, nvidia 346.xx binary (tested) branch dkms. Adobe air/flash via winetricks. So yeah it is 100% launcher bug, not related to directx or unity or other desktop environment or even other operating system. Hopefully RIOT have some fix for these misbehaviour soon.
I'll try to do client repair later on, but it seems it 4.20 patch problem as many people all over internet raise these bug reports.
Also I edit Config/game.cfg and added line for OpenGL rendering there for my linux system:
[General]
x3d_platform=1