Hi Shiva,
It is the inner Eval() that is causing errors. Here's the edited XPath. It creates the same error:
xdMath:Eval(../my:associates/my:individual[my:profile/my:matrix_assignment_code = 'kc'], 'concat(my:profile/my:name, xdXDocument:GetDOM(''characters'')/characters/@cr)')
Nonetheless, as a curiosity, I removed the kc from the XPath and ...