Hi, this one is an easy fix. Go to the product page...the one where you set up the product originally.....scroll down and set "price by attribute" to true and then remove the price in the boxes below that...then preview...then update.
Understand that currently the cart can NOT track stock by attributes. So if you have 150 bowl (50 xsm, 50 sm, 50med) and you sell a med one it will remove stock from the 150 total. This functionallity is supposed to be in the next major update.
I would also go back into the attributes controller and go to the little box with the + in it and clear that box. Also change the sort order so that its x-sm, sm, med in the dropdown instead of med. sm, x-sm