Here are my instructions!
1. Draw a table.
2. Place a cell inside of it.
3. Insert the flash file into the cell. - Make sure the table is big enough.
4. At the top of the table will be a label thingy or something, right click choose from the menu Align > Center.
5. If you want to align the flash in the cell select the frame of the flash file in the cell, press the right key and in the properties inspector select center justification.
If you didn't understand that well I may have to provide images.