Error between demux and bus creator port dimensions

Hi,

I am getting the following error when I run my model:

Invalid setting for output port dimensions of 'aircraft/Aircraft/Interface/Bus Creator1'. The dimensions are being set to 4. This is not valid because the total number of input and output elements are not the same

Invalid setting for output port dimensions of 'aircraft/Aircraft/Interface/Bus Creator1'. The dimensions are being set to 4. This is not valid because the total number of input and output elements are not the same

This comes from the blocks shown in this picture:

It is odd because all the port dimensions add up until it gets to the bus creator. The same thing also happens if I replace it with just a mux:

Error in port widths or dimensions. Output port 3 of 'aircraft/Aircraft/Interface/Demux1' is a one dimensional vector with 1 elements.

Error in port widths or dimensions. Input port 3 of 'aircraft/Aircraft/Interface/Mux2' is a one dimensional vector with 2 elements.

This "Euler" input comes directly from the 6 Degrees of Freedom Simple Variable Mass Equations of Motion from the Aerospace Blockset.

I would be very grateful if someone could explain why this is happening andhow to go about fixing it.

Thanks,

Ryan