Thanks to Michael I corrected the mistake. I spent lot of hours today till finally got 90% done. I do have still 3 "grooves" I can not fillet between each other.
Please note the attachement.

I also uploaded the full model in order to avoid the inconveniences pointed out above.

Thanks so much, I want to clarify I am loving MOI. It has some great improvements regarding Rhino in terms of how easy is to create non-buggy surfaces.
I am not an expert, but doing exactly the same procedures in both softwares MOI gave me much nicer surfaces :)

https://we.tl/tw80MOEnqe

I needed to upload the file in we transfer (was heavy).


Edit: I fixed one of the grooves. If you check the new attachment you will see what happens between those two there : )