Place / add two matrices of different size together

Building stiffness matrix I needed a function to add one smaller matrix within a larger one. I've added some functionality to that just out of interest. Now the second one can be added or it can replace the first. It can also be fully or partially outside the first and the original matrix can either expand or the latter matrix can be cropped. Seems to be ORIGIN-neutral too. No guarantees, so test it first. Have fun!

Mathcad is Prime 9.