about your new problem... um... you didnt tell us if that's Poly's/Nurbs/Subs...

if it's Polys, there are a few ways... you can select the outer edges that you want to connect and go to Edit Polys, and "Merge Edges"... then you can combine the 2..(not sure if you have to)

then the second way is to use the Split Poly Tool and cut along the corners a line of th bottom peice and then merge their Vertecies....

-Emo