What exactly do you mean by "Complex Hatches"? You can create new 'materials' for RAC utilizing ACAD Hatches, both Model and drafting types, and yes they would come from the acad.pat file, which is text based.
You might also try this:
Access a broad range of knowledge to help get the most out of your products and services.
Start with some of our most frequented solutions or visit the Installation and Licensing Forum to get help installing your software.
Upgrading to a 2015 product? Make sure to check these out 1st!