We have been chasing this one down the past couple of weeks, and we found we had an improper motor current called out on the extruder in the firmware. We now have marlin 1.1.9.34 available in Cura LE 3.6.3. From our testing this modified current fixed up the skipping issues. We are still in Beta with 3.6.3, but if testing goes well this week we will release next week. You can try it out here if you like: http://devel.lulzbot.com/software/cura-lulzbot/
Ahh this could be the difference! Each vendors specific blend of PLA has slightly different thermal properties. We did not do any testing with Verbatim PLA, as we didn’t quite have the bandwidth to get every blend tested and verified.
With Marlin 1.1.9.x we require the user to home the printer before movement will be allowed. There is then a software max travel position we use to limit travel, so the X max switch is not required. Have you had any issues with moving the tool head too far?