Hi,
Thanks for your suggestion, but unfortunately this problem goes beyond of the possibilities of Glue, because the plugin must not only to move the objects along a generic axis (that may be a interesting new feature, not very difficult to write), but also must detect the collission between the geometries. Glue works using a XY plane to place the objects, but the surface of the cylinder is not a plane.
Btw, sorry about my english too... it's not my native language because we are from Spain