Changes made to multiple cells at once not tracked
I filed this as a bug report earlier but thought I'd explain it here in case someone was interested. This has probably existed since CS3 when you could first track changes in tables. This can be reproduced in InDesign as well if you're working with ICMLs.
If you are using track changes and make a change to multiple cells (by copying and pasting) these will initially be tracked. However if you save the document and then re-open it the tracking for these changes is gone.
To reproduce this:
1. Create a table in InCopy like this:

2. Select two cells:

3. Paste the contents of these cells in two other cells:

4. Initially these changes will be shown in Galley/Story view as tracked:

5. However, as soon as you save and reopen the document they disappear:

This basically occurs any time you copy and paste from more than one cell into two or more cells. (It works as expected if you do one cell at a time.) So if you move an entire column or row in this manner, or add rows and columns and move content around, it will not be considered a change once you save the file.
