Allow me to simplify the art licensing process for you so that it sounds less terrifying.
The main concept behind this part of the process is to come to a deal that is really mutually beneficial. It's totally possible. Both sides are likely to start out asking for everything they could possibly dream of, but as you go back and forth you can slowly let go of things that are less important.
Don't proceed with any numbers until you know what they need. And they're going to want to know what you need to. Oh, and read through to the end to know what you should NEVER EVER (EVER) do.
How to prepare for licensing and three ways to show your interest to a licensing company. Develop your own style for showing interest and thus beginning a relationship. It could be one of these or it could be a combination of the three methods.
A post mortem doesn't have to be very formal, but you want to take note of what went well, what didn't, and ideas you have for future licensing deals. Here are some questions I like to answer in a post mortem.