It's getting better and better - you are scaring me ... now I got to do something better :) Finally the contrast is in good balance since it includes everything between white to black.
Adding things like doors is probably easier than the "trivial" but tricky things like: jumping, to prevent sliding down slopes, and other little things that usually make people get stuck. For a trigger you probably only need to make the doors pickable. The same goes for pickable stuff like items, boni, medicine, ammo etc. Add some IFs and THENs and there you go.
Particles look nice!
Adding things like doors is probably easier than the "trivial" but tricky things like: jumping, to prevent sliding down slopes, and other little things that usually make people get stuck. For a trigger you probably only need to make the doors pickable. The same goes for pickable stuff like items, boni, medicine, ammo etc. Add some IFs and THENs and there you go.
Particles look nice!