Q: Different FFT spectrum - jit.matrix, jit.glue, jit.world
The error message is quite self explanatory, the matrices you send into [jit.glue] don't have the same number of planes, hence the error message. Another problem is that they don't have the same dimension either.
Spectrum 1 is a 1 plane 1x256 matrix.
Spectrum 2 is a 3 planes 250x256 matrix.
You want them both with 1 or 3 planes and with the same dimension (preferably the largest one in your case).
Here I made them both 3 planes 256x56
Max Patch
Copy patch and select New From Clipboard in Max.
Oh and you had the wrong number of rows and columns in your [jit.glue]
[jit.fpsgui] is useful to debug such situations.