I am disappointed at myself for not having tried to blow up the rocks in the tunnel under the machine, it was easy to solve. Since I already destroyed them with the laser gun to collect the acorns in the room behind in a previous exploration, I forgot the blocks that I was not able to destroy with the laser gun in the line under the ceiling and I paid no more attention to them on my next explorations on the planet.
I had thought of using the crates to block the flames but I tried to stack them on the ground, I didn't think of dropping them on the levitation pad to get them reach the ceiling, nice puzzle. ;-)
I actually thought of pushing a teleporter on the other side of the tiny tunnel with the fan but I tried to drop the fan on the ground, here again I didn't think of dropping it on the levitation pad to make it reach the ceiling, this is really the trickiest puzzle of the game. :-3
So the 3 only puzzles that I didn't solve on my own was because I paid no more attention to something that I noticed previously but forgot and not thinking of dropping tools on the levitation pad. :-3
And why is there a poop? I thought the last species that I was missing on Rii-Gosa was the one who dropped it but there was no such species so who dropped it actually?
Also, I found the 38 species, I collected the 20 tools and the 535 space acorns but my game progress is at 78,10%. What am I missing?