I can't reproduce problem (1), which is BEFORE you pick. I placed a featureline adjacent to the pipe with the same elevations and used it's quick edit hoving. From what I see it shows the same labels the same way (except our graphics are easier to see on a white background). Also press F1 to review the help so you can see what our intensions are.
I think we found problem (2) and fixed it, try tonights build.
We still need to add traps for values that push the pipe out of the range of the begin/end structures. If the value is lower that the stucture, lower the sump value and indicate this on the command line. If the value is higher than the rim perhaps just a warning [Alert Dialog] because raising the rim above what was likely already surface is not going to work, right?
What if pipes don't end with structures but instead join other pipes? Change the inverts of the other pipes without checking the impact of that? As I said, it feels like a cascading problem could arise.