FCPX and C200 Cinema RAW Light

Anyone running into issues with FCPX and Cinema RAW Light? We are cutting a project with a couple of hours of footage in this format. We are keying green screen and layering effects on an a top iMac 5K. It seems we have intermittent crashes that the crash analyzer blames on Graphics Card or the Canon RAW plugin. We have had done everything recommended right down to wiping the mac and reinstalling. We have had to copy project into a new library to keep working. We are working with the RAW optimized and tried every trick - deleting all render files, preferences etc. . Any thoughts?