After some help from a user, I figured out what it was.  It turned out I never had 1.2 installed.  I don't know how to go about making this post solved, but It is solved!

I am on mobile so I can't get the link, but I'm pretty sure it was thebritresistor on youtube
edit: Got on my computer and found it. https://www.youtube.com/watch?v=p7tYnd29q28

Missing models... in WHAT exactly? The Radiant editor, in-game, the files?

It is while compiling the level

zNi...

Hey, sorry if this has been posted before.  I am missing models for things such as the teleporter, perk machines, power switch and other things like that.  If I could get some help it would be much appreciated!
(This is my first map by the way, so sorry if this is a simple fix)