hi guys, while not a fix, i did figure out a work round. i created a seperate table with the coloumn headers in one coloumn and a second coloumn with number of chars rerequired for each coloumn heading (i.e. "xxx1 for column 1 which will format to 4 char width) I then linked the tables using the column headers. using the second column allows me to not only stop the autoformat from changing the table, but it also allowed me to select "show all items with no data" and have it work correctly. the final trick is to make the text of the header the same as your background, then create a card with the headers you required, place the card over the table headers and there you go.
hope this helps some one out, it was bugging me for most of the morning. an example of this is attached.
(a fix to sto it autoformatting would be so much better though....)
cheers
D