Is it possible to change the colours that the constraint tool uses to highlight the parts you have selected?
It's currently set to green and red but I use a lot of green parts so it doesn't really help.
I think you can do this if you install the Color Scheme Editor. It is located in the SDK folder in Program Files. Here is a snapshot of the editor and the folder it is located in.
You definitely will need admin rights since the program will modify the registry. I have used it and it works for me but I am also an admin on my machine at work.
I checked and I am an admin. On the colour editor I click save and nothing happens.
I've tried it with Inventor open and Inventor closed.
Look into using Inventor Color Scheme Editor found in the "User Tools"
You might have to run the "UserTools.msi" to populate the "User Tools folder... once you have the "User Tools" folder availible browse it, then "ColorSchemeEditor" folder, then "Bin" folder... in there you will find the "InventorColorSchemeEditor.exe". Run it.
Windows 7 users can find here: C:\Users\Public\Documents\Autodesk\Inventor 2014\SDK