Setting a value

I have a setup that moves 4 planes by calculating their positions over time. It works OK as shown. However, I would like it to be applicable to images of arbitrary dimensions. So, I calculate xscale when I load my mov file and send it as a float to this portion of the patch. However, this produces weird results that do not match those produced with the xscale bits disconnected, as shown. I thought connecting xscale receivers to the right inputs of floats would work but it does not... Any idea what I am doing wrong?

Thanks.