The bed channels should be assigned to the sends in the following channel order  L = Send 1, R = Send 2, C = Send 3, LFE = Send 4, Lss = Send 5, Rss = Send 6, Lrs = Send 7, Rrs = Send 8, Lts = Send 9, Rts = Send 10.   When using a multi-channel aux track "unlink" to assign each channel to the appropriate send from the channel drop down menu under the link button.