The Replace / Update Cell tool allows the user to select a Cell on screen to use as the new, replacement Cell. It accepts but stumbles when it can not find the Cell as named in the attached library. Replacement Cell vanishes. No error message.

This helps no one.

The tool should use the Cell selected (info is in the active dgn) and replace/update the target Cell(s).

If the Cell is not found in the external library, the internal Cell would be used. If there is one in the external library, the user should be given the option to choose. The message queue should list the source and name of both replacement and target Cells.

If the replacement Cell is a Graphic Cell and the target Cell is a Shared Cell, then the user should be asked to if he would like to save the replacement Cell to an external library, before adding it to the active dgn as a hidden model (current Shared Cell practice).