Has anyone been able to use the non-linear optimisation option in Calc with more than two variables without crashing the app?

[Calc2009]

I attempted to perform an optimisation calculation using Solver (non-linear option) with five variables and the following constraints:

1. sum of the five variables always equals 100%
2. all five variables must be greater than or equal to zero

I’ve performed this optimisation calculation countless times in MS Excel (with at least triple the number of inputs) and it works every time.
However, when I try to perform the exact same calculation in Calc, the app freezes up and returns an error message after a while, and sometimes it just crashes.

Functions used in the model are pretty standard (e.g. sum, average, standard deviation, covariance) and they work fine with manual input.

[Lupp]

Please supply an (crashing) example file containing a screenshot of your settings dialog.
What solver did you select?
Yes, I used the a nonlinear solver recently more than once sucessfully with more than two variables in Calc.