The dimension tool doesn’t work on round objects ie. to determine length of a cylinder or the depth of a circular form.
I have attached two files the docx file is a series of screen shots showing where I had problems and I have attached the skp file. I have also had a problem with the pushpull tool. I have put two tee slots in the tops of the mill vice blocks and the RH one no problem. LH one it had like a ghost affect on it when I pushed it through. I erased the Tee slot and started again but got the same result. I erased it again and then rotated it through 180 degrees, drew the Tee slot again used the push pull tool and it worked OK.
I hope these items help, 17 is better than 16 it seems more stable.
Ps How do I put the sketchup drawings in my email like you have.