Sheet metal bending and corners

Hello. I am trying to bend a simple piece for my 19" to hold some routers. Ultimately I will send the drawing to sendcutsend for fabrication but am having issues. I can design and bend the piece no problem but when I upload it, I get errors that the corner reliefs are not large enough (despite setting them to the sendcutsend minimums). And when I finally do get the corner reliefs inserted, the upload gives me a error that I have thickness inconsistencies.
I have done several parts with edge flanges all the same size (equal to the base flange) but when I attempt a sketch bend (because of the extended side), the problems in the corners arise.  I am at a loss as for what to do....

 

Edu SOLIDWORKS