Ya sounds right to me.
The buildings are great! I have a buddy who has access to a printer at his work. He knows WAY more about all this than I do...but basically...
There are loads of websites where people upload 3D printer blueprints they've made, free for download and personal use. We got some sim-city buildings someone had posted and using an editor (also free online) scaled them up to a good size.
Since printing off these my buddy has been using these free editors to make his own custom buildings for epic. More square and flat topped with gothic-style arches.
But like I said I know very little about the process. A little google searching will get you to these sites, they're great. Even if you don't have access to a 3D printer there are loads of companies online that take print jobs. With eBay and swap meets being the only source of epic buildings 3D printing seems like the way to go.
I was blown away by those buildings and they make the table look great. I basically harassed a fellow player in my group into printing off another set for me
So far I just dry brushed them grey. Considering battle damage and or imperial icons / banners to make them look a tad more 40k.