How about posting a database map? Data Tree - whichever you want to call it. Your company posted one once for a the Database Starter kit. Was very helpful. I don't think that's a lot of customization. I just want to know how the database maps out and what's called where. That's super basic stuff.
Site Map. Same thing. Layout the page relationships with page names and how they inter-relate. I'm guessing it's far to much for your customers to want to have a site that isn't WebAssist blue? Is that what your referring to by "modifying PowerStore to do something it doesn't currently do." It currently displays everything in blue. Why can't you guys just map out which CSS docs control which pages same for modifying your templates. I'm not talking major modifications - I just want to see how the site inter-relates so that I can change a basic background color. I'm certain that other users would want this ability as well without spending a week with Firebug reverse engineering the CSS of the site!
Also as far as the documentation goes - when you are installing the site it asks for the PayPal User Name and Password. Couldn't a one pager be created explaining that this is the API User Name and Password that's being asked for? I'm just stepping backwards for users who aren't so advanced. It doesn't say that anywhere - and yes, that's confusing.
And adding products to a store shouldn't be considered "customization" of your store. That should be the DEFAULT thing that is a "How To Use PowerStore 3." That is after all the main purpose for buying the store! Customization is changing the color of the navigation or the logo images and font and home page background.
The directions if followed on this page: signup_usps.php
cause your store to not work due to the fact that the page you're directed to gets you a testing credential with the USPS and the PowerStore 3 software doesn't work with that.
Also a Known Issues forum topic is very much needed right now for PowerStore 3!!!