Working on this right now! 
I redesigned the box so that all of the walls are a multiple of 3 of the default extrusion width (.6mm). So all the walls are now .070866" thick. The gcode preview looks promising. I’m printing right now!
IT WORKED!!! 
The 10th time is a charm! hehe
I would have never figured this out without all of your input! You guys rock!
Shout out to Gapdev, kcchen_00, and DougZ for all the help! You’re all awesome!
Niiiiiiiiice! Great job!
I just wanted to thank you guys for the info you’ve shared.
I was having trouble with a part I was trying to print, and some of the changes in S3D you discussed helped me solve the problems.
Great, glad you were able to get something from it!
Coincidentally, I just printed a GoPro item I’m designing and am having the same thin wall gap problem now. Go figure!