Boot failure on 3.1 mac pro KDE plasma install

I have just joined, I wonder if anyone can help me?
I have just attempted to install KDE plasma on my mac pro 3.1
the first part of the installation went fine without any errors - I could boot from the usb stick without issue.
However, when I reboot after install it fails with massages such as failed to load shared library etc.
what should I try?

mac pro 3.1 2008 8-core Xeon 32gb of ram radeon hd 7950 3gb install on internal Sata bus