One of the lesser know, but very useful functions of EditLive! is the ability to customize the spelling dictionaries. This allows you to add domain specific words or specific company titles that your authors regularly use. We've had an article in our documentation for quite some time on how to do this, but with all the options to configure EditLive! it often gets missed.
So, if you're sick of that red squiggly line, take a look at Creating, Modifying and Adding to Dictionaries, one of the hidden gems in our documentation. It's actually quite simple.