I am new to building a model train setup so please bare with me with some of the questions I know I'm going to ask.  Here is one of my first major problems.
I have two left turnouts and two right turnouts connected together so as to connect an inner track and an outer track.   When I run the train different cars derail.  I'm having a very hard time figuring out what is happening.  Any help would be greatly appreciated.  I am trying to put this together on a 4 X 8 layout for my two kids.  The frogs are plastic.
These are the turnouts I'm using.
http://www.bachmanntrains.com/home-usa/products.php?act=viewProd&productId=194
Product Code: 44561
http://www.bachmanntrains.com/home-usa/products.php?act=viewProd&productId=195
Product Code: 44562

Thanks for any help.