Optimum Modpack

There might be an issue where waypoints are not saved between updates. So, you might want to save the coordinates before updating or some other form of saving them like placing waystones to those places. Other than that, I haven't encountered any issues so far going from 2.0.0 incrementally to 2.1.1

Updated:
CodeChicken Lib 1.8.+
CoFH Core
Ender Storage 1.8.+
Forge
MineColonies
PneumaticCraft: Repressurized
RFTools Utility
Thermal Expansion
Thermal Foundation