I feel that sometimes the music get satured by the end, is it just me ?

I get the idea of trailer to promote full payable product. But I don't think that removing the audio count as such. In fact, audio is part of the core of a video. Without it, it's equivalent to un-finished work and should be treated like it.
I am not asking to your full product here, but to post video that have image and audio. If you want to promote your stuff, you can, for example, created clip of the full product and post it here.

I think there is a lack of transition and ambiance sound.

Great game!
But I think the problem with the list of word, was a bit far fetch, like I've got the letter , what tells me that I have to find a word with and not just throw them to the chest.

On level four, tom spawn on me immediatly making a game over

Very good little game, with fun mechanic!
I've appreciate a lot the fact that controlls adapt to azerty keyboard!

Very great song!
I just have two minors comment :
- I feel like the radio voice should be edited like those around ~2min or at least being Sync with the song because they kinda pull you out of the music/ambiance
- I didn't feel any impending danger like mentionned in the description. Like I said, the music was great, but not in the theme that you'd seemed to wish (except for the final part)

Les petits bateaux nagent, nagent, nagent, nagent comme il faut!
I find the origanl melody! XD

For a moment, I thought the thing between the feet of the blue guy was his underwear! Making everything weird!

I like the position you put her in, but I think there is a problem with length of the neck and her right shoulder.

It very well drawn, but I think the shoulder is not place where it should be. It seems a bit too much on the left (or peharps it's the head who is too much on the right), even with the sensation of burden.
There is also the top of the legs who are too flat with the upper body.
But again, I love your art style!