PRint quality on larger prints

I've had my Zortrax M200 for about 2 weeks and mainly printed smaller things to try it out. The print quality has really impressed me!

Over the last few days I started printing a head scan in parts. The first part was the face and it was about 14 cm x 12 cm and almost 10 cm high. The print quality has been awesome on all the prints so far, besides when I've been trying to print in Mesh or Shell mode. Even though the quality on this face print was good, I started seeing quality issues that I haven't seen before. I'm just curious to hear if anyone has had similar issues and have found ways to solve this problem?

The zcode I used was 0.09 mm, normal print speed, low infill, random seam. I have sidepanels on my printer and use Z-ultrat filament.

Is it the first time you print at 0.09 ?

Maybe the random seam is not a good choice. 

This is not the first time printing at 0.09., it has worked beautifully before. The random seam choice could have been a problem, but I'm sure it's not the only one. This was printed with low infill and I think the problems occur mostly because of shrinkage.  With such a large volume, and the infill tying every part of the outer wall together, the shrinkage affects the volume in all directions. And as the piece shrinks while being printed the new layers won't line up.

Since I posted this I tried hollowing out the 3D model to 10 mm thickness and print with 50 degree support lite. My thinking was that the support is needed to hold up the inside of the model, but support is not attached solid to the outer shell and the shrinkage wouldn't be strong enough to pull the walls together. Big hollow shapes with an open side will always warp slightly however you make them. But with the print it did work a lot better! A lot less surface problems (even if I didn't save as much material as I would have hoped).

Unfortunately I don't have a  good picture of it, I ran out of grey filament and had to print it in white Z-ultrat.

I also noticed that the force I have to use to get the piece off the platform can make the piece warp unless it is absolutely cold.