Mathcad Prime 3.0 READPRN not working properly

Hello,

I am having a trouble with the Mathcad Prime 3.0 function READPRN.

It is just a simple test atm. I first define a Matrix, write it to a file with WRITEPRN and then read it again with READPRN. It works fine as long I use standard two dimensional matrices. But I need it to write/read a matrix whose elements are matrices themselve ( I thinks its called nested matrix). Anyway, the WRITEPRN function works fine again, but the READPRN causes the Mathcad to crash most of the time. It shows me a windows error message saying "PTC Mathcad Prime 3.0 has stopped working" and gives me the option to close the pogram.

I would really appreciate some help on the this issue.

I am using:

Windows 7 Enterprise SP1 64 bit

Mathcad Prime 3.0 64 bit (Trail Verison)

Attached is a example that is not working for me. (prn_ex)

EDIT: The second example is working. (prn_ex_working)

Thanks in advance

Eric