After upgrading the ChemOffice Worksheet (which is created using a previous/prior version) you encounter issues when trying to edit the structure by double-clicking on the structure in the ChemOffice worksheet and may receive an error similar to the following:
If so, you are trying to double click while placing the mouse cursor over the structure, without selecting the cell, or after selecting the cell when the cursor has a palm symbol as below:
You can edit the structure in the ChemOffice Worksheet only if the cursor symbol is a + symbol, and not a palm symbol.