I keep having issues with Lightroom Crashing during upload.... I updated my mac to Serria and it keeps doing it... Idk what to do!!
Make sure you are updated to the latest 6.7/2015.7 if you are using LR 6/2015.
Known issues: Known issues - Running Lightroom CC on macOS 10.12 Sierra
You may also want to try to deactivate the GPU acceleration: Adobe Lightroom GPU Troubleshooting and FAQ
Retrieving data ...