Cannot evaluate expression because a native frame is on top of the call stack

The error message is trying to tell you that the thread is currently executing unmanaged code, and therefore cannot be used to evaluate the expression.
Basically, the execution has hit a problem in kylix code rather than yours and can't examine your variables because they aren't directly available - and the kylix code isn't built to be debugged so it can't look at that either.
So start by looking at what you called and what you passed to the component - chances are that you passed the wrong thing and it crashed as a result.

We can't do that: we don't have access to your code, and even if we did we couldn't run it under exactly the circumstances you do!