Yes, and to answer
How am I able to setup a email alert if a link hits 90% usage...
It can be done, Use the rate function. How to use it is another story. As always there is probably a better way than the one in the probe thread. They changed how it works as well so look at the beta thread if you are running it.
A great seemingly un-noticed feature of the link setup is manipulating when the line 'goes red'.
I have all the gig links set to go red at 50Mbps. That is the only way to see if anything is going on.... and it is always the network is slow, LOL.