It would be incredibly helpful if Tab and Shift-Tab moved you to next/previous cell in tables
Currently, it is rather inconvenient to move around in the tables. The arrow keys work great for moving long distances vertically, but there is no quick and easy way to advance one cell at a time.
MS Word (and other word processors) allow you to use Tab to advance to the next cell, and Shift-Tab takes you back. This is far easier than moving your hand over to the arrow keys or to the mouse.
The current behavior of Tab and Shift-Tab when editing tables in GUI mode is odd (I haven't figured out what it's doing). But whatever its current purpose, I doubt it is more helpful than cell navigation. I'm constantly finding myself hitting Tab to go to the next cell, and the whole table is now selected. There is no keyboard way (as far as I can tell) to get the cursor back to editing a cell, and it repositions me to the top of the table. You have to find the where you were and click on it with the mouse.
Maybe this should rather go to FCKeditor project feature requests (if not to browser projects feature request - I don't know exactly who has control over that, but it is not a moin feature).