Why don't you attach a Mathcad worksheet. Would be better than a Word document.
Mathcads symbolics has its weak points and may not be able to measure up with Mathematica and Maple.
But are you sure about your integral - the solution does not contain rho anymore but a z? z is the variable of integration and so it should not be present anymore in the result.
Does the following look familiar?
BTW, I see you still have an unanswered question pending http://communities.ptc.com/message/221911#221911
