I have used the Crafter's Pick Ultimate since June 2013. No problems with the glued pieces coming apart. No yellowing of the glue so far. It has a consisency of thick pva glue or acrylic caulk.
Here is a picture of a fresh bead of the glue on a vertical piece of glass. The bead is approximately 1/8" wide or around 3 mm .

cpug bead.JPG [ 89.16 KiB | Viewed 28121 times ]

Personally I found that the Brush on krazy glue works really well. Strength of super glue, doesn't require much to work, and it doesn't cause warping for the most part. Just make sure you have good airflow/ventilation in your working area is the only down side I've found. Pretty easy to find at walmart/staples/etc.

I've seen the UHU separate from humidity. Epic Fail for builds in my tropical paeadise...

I have been using the UHU Twist and Glue for about six months now and I have to say it's excellent. No warping, great applicator and seems to keep the bond strong during storage. I am very pleased with it.

Has anyone had success using double sided tape instead of glue? Maybe the zero water content would be helpful?

I began using 2-sided tape for my floor/ground tiles a while back, and they've held up with no issues. I haven't tried this with anything else.

I use things like and it works great.

I use glue runners like for all sandwich folds now and I don't have issues with warping. That's similar to double sided tape, but not 100% the same.