Fiddling with objects that have way too big or way too small a radius of influence. Yesterday I was trying to move a few trees and every tree would move except the one I wanted, even trees that were many meters away. Multi industry track is another culprit. Had a nice freight warehouse set up and was trying to add some signage and clutter every time I tried to rotate or move anything the track moved. I tried every angle and direction know to man and eventually got it but I'm sure my blood pressure went up more than it should have. Conversely, some items are just about impossible to more, rotate or delete unless one gets lucky enough to find the invisible sweet spot.
Yup on both! I ran into this yesterday and gave up adding in the small asset I couldn't grab and adjust. The layers do work for the bigger items though. Move the item you don't want to move to a layer and lock it. When done do the properties on that object and move it back to your route layer. I have this setup and it works great.