For the most part it has been working smoothly for a long time on my MacBook pro. I have the most recent update and most recent OS update on the mac. Yesterday upon importing a small batch of images the screen started jumping around and was full of lines, all kinds of stuff, I had to shut down the computer to get out of it. I then force quit LR and tried to reopen it, same thing happened. Can I delete LR and reinstall it? I also have subscribed to Photoshop CC which is on another computer, can I transfer the subscription over to my Mac from my PC?
Yes, you can delete Lightroom and reinstall it. You won't lose any of the work you have already done because a reinstall will not replace the catalog that you have already started. Since you have subscribed to the Creative Cloud you will have Lightroom CC rather than Lightroom 6 and that will give you access to additional tools and features that were not available to you previously. It's the same program, actually. It's just that you will have additional features running under the Creative Cloud subscription.
This sound more like a Computer Problem. Do you have the option to use the GPU turned on? If you do turn that off and test.
It sounds like you have it turned on and the discrete GPU is causing the problem. Apple is known to have discrete GPU problem since 2008 with many if not all MPBs.