Z87X-UD7 TH - Can't reach the installer screen

Feb 4, 2014
Gigabyte Z390 Designare
GTX 780 Ti
You can see my system below my avatar, it's basically the Yosemite 10.10.5 OS installed with Clover that runs on the Z87X-UD7 TH motherboard, i7 4790K CPU and the 780Ti GPU.

Now I've made a UniBeast 6 El Capitan installer USB and I just can't reach the El Capitan installation screen. The first time around, after I've clicked on the USB installer in the Clover startup menu from the USB itself, I wasn't sure what happened. There was some kind of installation going on with a percent number indicator. Afterwards I've chosen the normal MAC OS X startup disk and there I've encountered the "Missing Bluetooth Controller Transport!" message in the verbose mode.

I've tried various bootflags, such as -f, -gux_defer_usb2 -gux_no_idle, and I've also tried this single user, verbose mode code:

Type: mount -uw /
Type: cd /System/Library/Extensions
Type: mkdir intel_back
Type: mv AppleIntelHD* AppleIntelF* intel_back/
Type: touch ../Extensions

Reboot -v

It didn't work. Now, when I try to make a reinstallation (not sure if there was one in the first place), I also encounter this message when I use the USB in verbose mode. Is there something else I might try?