
All it is, is a mini-game that was added to where you can go to a new area accessed by the boat behind the Al'Kahrid bank. Anyone can play it, the demo is just for people who are new to try the game out. When you go to Daemonhelm you can go into a dungeon with up to 5 other players and go down to new floors whenever you level up your Dungeoneering skill. you can also aquire tokens from the dungeon floors and spend them on new and better items at the shop in Daemonhelm.
"Dungeons of Daemonhelm" is simply the location where you train the newest runescape skill, "Dungeoneering." Dungeoneering is available to both free players and members, however it is just one of many skills throughout the game. Members have many more options and easier access to skill rewards though.
It's an awesome new skill where you get to raid dungeons by picking a dungeon up to around level 40, slowly advancing through floors. then, the complexity can go from 1-6. Level 1 complexity can be run through quite easilly. Level 2 requires only a bit more skill… Level 3 is a new complexity… but only for the new ones who have had at least a bit of experience. Level 4 is a basic complexity involving a wider variety of skills. Level 5 complexity is fairly long, but still not THAT long, compared to 6. 6 is the same a 5, a little harder, but has no xp penalty. Hope I helped. that is the basic overview.
Dungeons of Daemonheim is basically the name of a new castle. It was released with the NEW SKILL (Dungeoneering). It is just there for a few weeks to decorate and show. The dungeons exist inside Runescape. (it is not a demo or anything else)