Hye Lukas! Welcome to the forum

Game looks and sounds great. It's nice to see that combination of bitmap imagery along with the flat more traditional animation look. It also has just a touch of that "Waking Life" feel to it (not surprising since Flash was used to make the movie!)

I think you're on the right track with it. Have you put together a storyboard for this at all? I think you'll find the assembling part of the process a bit easier if you have something to work off of - some sort of script.

As far as ideas of things to put in the game: there are so many possibilities in dreams as far as characters and objects that there really is no limit. However, I think you could try something like this:
[list]1--Create a scene with basic, empty invironment.
2-- In the environment choose some main objects that 'belong' there (if it's a bathroom, you'd have a tub, sink, mirror, etc).
3-- On these main objects, pick out some "hot spots" where different objects could appear or disappear randomly.You could have a library of movie-clips with code that loads them at random.
[list]
Essentially you'd have a movie clip (tub) with other clips inside them (hot spots) and a counter on the main timeline picking out which clips to load or unload and when.

I can't wait to see how this develops! I've thought about making a game myself but I had trouble with coming up with a concept (and quite honestly, I just have too many other unfinished projects floating about!). Seriously, if you ever need some help with this don't hesitate to PM me -- I do a lot of work with Flash.

Good stuff

PS-- I've noticed in your sample that the "wind gust" thinggy that comes in when you click on the sun appears to be playing at all times - are you using the opacity to control it's visibility? You might be better off having the clip go to an empty frame or using the _visibility=false code to hide it -- the movie will play a bit smoother if it doesn't have to continuously process that clip.