Warning, spoilers ahead!
I finally got to play some more and finished the marsh today. This game is really fun! Looking forward to the final version tomorrow. :-)
Anyway, there is one thing I noticed. I found 6 out of the 8 levels quite easily and then I was a little stuck. Following the hints I finally managed to find the clearing with the "real" grave of Juan and the keys. This enabled the entry to the warehouse facility, where I found a portal and the green key.
So I thought to myself that the last missing level would be in the building with the green door. But when I reached it I just found a bike.
Chasing around I finally noticed the hidden sidepath to the south of the clearing and could start the last level. It was the snow highway and I think I died at least once in there.
However, when I returned, my bike was gone - and the green door was again locked. Is this intended? I decided against travelling back to the warehouse and just went by the shooting plants without a bike (which is perfectly possible, there is just one point where a red plant jumps at you and you can't really prevent it).
I had thought that the color coded keys and doors are unique and that opening them is persisted somehow.
Anyhow, thanks for the great game! Now on to the snow hills. :-)
