Sorry but:
"Parameter unknown Pan Parameter"
So maybe this is from A7 Beta or something?
Becouse I can't find such a things even in online help LINK

And easyer will be with f.e.
bmap_rotate(bmap_name, vector); or something like this
vector[2] - x,y coordinates of bmap, so You can choose center point of rotating

or just
bmap_name.pan and implicitly it'll be a center of bmap or showing window if any