Dungeoneering on Project Dream can be accessed using the teleports tab (Quest Journal), then clicking Skilling Teleports and then followed by Dungeoneering. It is based in daemonhiem and it has over 15 different floors to play which are randomly selected depending on your Combat Level. When you first enter the floor, there is an NPC called 'Smuggler'. He sells basic items that will help you on your journey through the floor. He will also buy any supplies you collect.
Updates For the Future
It's inevitable as with everything on it's first release that there's the occasional bug or problem within the system. At the moment, there's definitely updates to come, with them, frequently occurring on a daily basis.