My little advice for SubD sculpt modeling in Moi :)
Rustic but like this you will not have problem and possibilities to sculpt many things inside MOi Itself!

When a face don't want SUbDivided; the face(s) is enlighted so SsPlit them (P = SsPlit )
Just copy Move a face (Select "Only one" face + Ctrl + Move) then Bridge it ( B = SsBridge)
(you can select many faces and Copy Move them but after you are obliged to Select only 2 faces for Bridge them!!!

Verify if solid object is subdivisible with K (K = _Subdiv_beta9 ) then Undo and continue to Modelize!

here the polygon has 7 edges! (that works ! :) (Don't forget the bottom face! )


Last function is SsScale for Move Size Rotate selected Points' Face(s)
(not Shown above )