Using LR 5.5 and now 5.6 causes Lightroom to crash constantly.
If I go back to version 5.4 all is well again.
Now that I have purchased a D810 I have to use ver 5.6 to get raw support.
I worked with adobe support for a few hours and finally gave up and went back to 5.4 until now.
It must be computer related, but I am not sure what the issue is.
Windows 7 ultimate x64
500gb ssd primary
other drives as additional storage.
Do I need to do a OS refresh or buy a new computer to make this work.
I'm having the same problem (D800E) and getting so fed-up I'm about to kick LR out. During a day I have 5-6 crashes.
I have a similar system as you have. I tried to most common advice to reset the preferences (very annoying) but still I have crashes
Looking at the web, LR has many problems since version 5.5.
Time to start solving the problem adobe