Well, yes and no. The 'ind' parameter is on a per tally basis, so if we are ok with calculating the offsets for every map, then this should be fine. This sounds best to do by saving a vector of offsets at each level of coord, which is akin to what the cell filter does. I agree that this is probably a better option.

As for the track_xyz, the issue was with crossing any surface/cell/lattice/etc. If I recall correctly, there was a problem with the coordinates I needed not being the same ones provided by last_xyz due to this. This was only a problem for tracklength tallies, so I named it appropriately.