Michelle sorry to hear of your leaks
. The good news is though that Trilliums dont have nearly as many rivets as a Scamp!! Also bellyband leaks
are not as common as you might think.
As Cam suggest remove the Fan and clean the area all up and reseat it - but use Butyl tape under it to redo it. Search this list to find lots of info on doing that - dont use silicone caulking on any of the leak areas as thats only a temp fix and you will hate trying to get it off when you go to fix the problem properly.
Keep in mind that the water leaks
can be hard to figure out where they are coming from so it may be that the water you see is all coming from the roof vent - the water will run under the wall covering in all directions.
are usually higher on the suspect list of leak points than the other items you mentioned, I would take a look to see if the weep holes/drainage holes are clogged - that will cause the water to back up into the trailer so you may not need to reseal the windows
just unclog the drains. I am not overly familiar with the window frames on the newer Trilliums but there should be small weep holes or a piece of plastic on the bottom outside of the frame that can be popped off to reveal the drain holes. Use the plastic weed eater type thread to push through the holes to clean them out. Then use a hose on the trailer one window at a time and have someone inside take look to see if they can detect any water coming in. You may have to leave it running for awhile before you actually see water inside.
Attachment points for awnings can be a problem area - especially if someone but excessive weight
or force on the awning
or left it flapping in the wind for long periods. which can loosen the attachment points. Again once you have proven it to be a problem using the hose technique its pretty easy to remove and reset using butyl tape.
Yes the wall covering is marine grade so it should dry out nicely without an longterm issue. Not sure what the strange smell you have might be. Has the fridge
door been left closed - those can get a bit funky if not left slightly open when the trailer isnt in use.
As Cam says take a deep breath the nice thing about our little trailers is that they are actually pretty easy to fix.