Quick follow up for anybody else in this Cross Sell boat... unless you can program, don't waste your time with Multi Cross Sell if you want a cross sell that works with TPP.

I installed Cross Sell Plus Advanced Sell, played nicely with TPP right out of the gate. It appears you can get around the limitation of "6 cross sells per product", too. In the configure, you can tell it how many cross sells to accept. I changed from the default of 6 to 150, have yet to figure out how to input the additional xsells, though.