Re: Can't get out of demo mode
From what you write I can tell you're using the Kontakt Player and Analogue Drums kits (even the latest ones) will only work in the 15 minute demo mode because they're not licenced by Native Instruments. They're fine in the full version of Kontakt because, as a paid for product, you can load anything into it. (I'll assume you realise that each time you restart Kontakt Player that you get the 15 minutes demo time).
Yes, it is very easy to load dry and room samples into Kontakt and have them play at the same time. All you need to do is change the MIDI channels of each instrument to be the same. I don't know what kit you're trying but here's a link to some very nice multi setups that somebody already made for Big Mono, Popsticks and Rockstock > viewtopic.php?f=13&t=425
If you find the 15 minute Kontakt demo mode too restricting you can always download the free Shortcircuit sampler and map your own samples (if you do this get v1.1.2 as v2 is very buggy and unfinished). Shortcircuit isn't as polished as Kontakt but for drum setups there's not much it can't do that Kontakt can (although it does take a little more effort).
Hope that helps