Symbolic Processor error when creating nested array?

When trying to create some test matrices in Mathcad 15 for the functions in the attached worksheet, I found that I couldn't create a nested array at worksheet level by setting one element of a matrix to be a matrix. 

It's fine if I do it inside a program or if I manually create such an array.

Is this a known issue?  Does it still exist in the latest version of Mathcad 15?

Thanks,

Stuart