Hi asilvestri,
Do you use the mididump with instances loaded in VE-PRO?
Mididump via Step Input should work when you send it from a slave computer.
If you are running VE-PRO on your Master computer it's not possible any more since Cubase 7.
This is somehow related to active status of the editor window in Cubase. Before Cubase 7 this has worked also when it was inactive. If you click Mididump inside VE-PRO you can not stay active in Cubase.
I already have talked to the Cubase developers to get it back, because I also miss this feature.
As far as as I know it's not possible to change the middle C defintion in Cubase. But it's possible inside VI PRO inside the "General settings". (the small icon on the left of the Version number). So you can set Middle C to C3 in VI PRO there. Maybe this helps to have the middle C defintion syncronised between Sequenzer and VI PRO.
best
Herb