I just recently changed out the OEM .5mm nozzle for my Taz 6, and replaced it with a .4mm E3d v6. Since the change I have been seeing not so good layer adhesion or layer separation about 9 - 12mm from the build plate. Currently printing with Alloy 910, did not see this before the nozzle switch. The material has been dried. What would be some things to look into, to try and make this better.
You made sure to change the nozzle size setting in your slicer right? What layer heights are you using? A smaller nozzle will not work as well with thicker layers.