related to that cell (since elements are usually temporary and so
kept in a separate list, not in the cell). Corrected a major error
in the bplane implementation that failed to remove a cell use from
the child def's parent list when deleting the use. Can cause magic
to go into an infinite loop, especially after selecting and unselecting
cells.
called the undo record generation twice when transforming (move,
copy, etc.) cell instances. This would cause the "undo" command
to regenerate the old instance position in the bplane records,
generally causing trouble down the road (did not encounter any
fatal errors, but it can't be good).
Tim Edwards