newbie question> cannot fillet or shel or offset this solid

 From:  Rudy
1260.1 
Dear all,
dear Michael.
Rudy here. I newbie in this world.
I am learning, so you guys bear with me. I know you are all very busy and Michael perhaps more than everybody (but I am ready to purchase when V1 is out), so do not get too mad at me.

I am having a problem to kake things happen with this solied (see attachment).

1- I would like to fillet the main rounded section, but when I select the main curve or even the whole solid, nothing happen.
Any radius is OK, as I just testing
2-I would like to shell the bottom of this piece, and also this will not work.
3- I can still make a shelling of the bottom, by offset the whole pice, but I have only positive results> It will offset only to a bigger piece. If I give a negative value, it will not offset it.

Am I doing things wrong?

Thank you all,
Rudy