RAW issues in Lightroom 5.4

Question

Hello! I'm having issued with my Lightroom. When RAW photos import they seem to be fine then after previews are rendered there is an error message on some of them (just a couple and different ones every time) that says "There was an error working with the photo". Also, some photos get crazy purple lines across them. All these photos open just fine in Photoshop and the RAWs are great on the card and in other programs.
These photos import just fine on another computer. So I've tested cards, card reader and computer. I've also reinstalled Lightroom and reinstalled operating system.
Problem is happening on Apple iMac on version 10.9.3 running Lightroom 5.4.

Answer 1

Is the problem intermittent with a particular photo, where if you remove it from LR then import it back the problem is gone or different, or if you delete it from disk and recopy from the card and reimport, the problem is gone or different?
There is usually something wrong with hardware on the computer, usually memory, if the same photo on disk renders differently at different times.
When you say the photos open ok in Photoshop, presumably you mean in the ACR plug-in on the way into Photoshop?
What happens if you use Edit In PS from within LR on one of the photos that looks weird in LR, does it show up ok?
The thing to determine is if the particular instance of the photo as copied to your computer is bad, so anything that opens it that is interpreting the raw data and not just the embedded JPG preview, vs the exact same file on the hard-disk opened in LR vs PS/ACR is ok in one but not the other.  This would show whether the file was bad or the computer reading the file or working with the file in memory was bad.