When working tables:

1. All cells widths must equal 100% of the table width.

2. All cells must have content, empty cells need to have either 2 spaces or
transparent GIF image to keep if from collapsing.

3. You may need to use nested tables (tables inserted in a table cell).

4. If you define you table using %, then you need to use % for your cells.

5. If you define your table using pixels, then you can use % for the cells.

6. If you define your table and cells using %, and then use your mouse to
adjust cells, you will fine in most cases that all the cell sizes are
convert to pixels.

7. Your table can be sized using percentages and your table cells too (this
comes in handy for different monitor settings too because the tables expand
and contract to fit) but you can't size artwork that way.

8. Keep track of those nested tables - if you need to change a table
setting you can't get to the bottom table very easily.