Hi guber,
To collapse an edge in 8.5, select the edge you want to collapse. Then goto the Edit Mesh Menu and select Merge to Center. You'll need to do the edges one at a time if you have more than one to collapse. After you collapse one edge, just select the next one and press "g" to repeat the last command.

To split a vertex, just select the vertex and goto the Edit Mesh Menu and select Detach Component. It only works if the vertex is a shared vertex, meaning more than one face is connected to it. It the vertex is shared by two faces, it will spit into two vertices. If it's shared by three faces, then it will split into three vertices, and so on.

Hope this is what you were looking for!