In reply to your keyboard issues, I use <bootmenu enable='no'/> to skip the first boot menu. This focuses the keyboard on the Enoch boot loader.
For passing the 25% mark on boot you need to add some boot flags at the Enoch bootloader. I used nv_disable=1 to fully boot. Then install the Nvidia webdriver. The webdriver won't work for 10.11.2 so you need to install and modify the driver with an application called NVIDIA® WebDriver Updater.app. On the NVDAStartupWeb.kext patch tab enter 15D9c as fake OS build. After installing the driver the driver thinks you're still on 10.11.1. I didn't touch anything else in the app.
After installing the drivers, reboot with nvda_drv=1 at the Enoch boot loader. I need to enter this at every boot which is annoying. I hope you don't have to.
Check out this post for the correct files in the /Extra folder: https://lime-technology.com/forum/index.php?topic=44908.msg429831#msg429831
ps: I also use a GTX 960 for the OSX VM. It drives 4 monitors (1*4K, 1*HD, 2*1600x1200) perfectly fine.
Working perfectly for my GTX 750 ti !
Download textwrangler and check your boot plist. Make sure textedit didnt add any garbage to it. If i used the one from the macfiles zip it added extra formatting garbage.
Once I used textwranger and only had the plaintext version from the guide it worked and no longer required manually adding nvda_drv=1
Which brand of 750 ti card are you using? I'm leaning towards the EVGA or MSI versions that have 1 fan because of the compact size. I also want to make sure that the GPU passthrough works for me.