This paper deals with the configuration of the static segment of a FlexRay network, in the case where the tasks producing the signals are not synchronized with the FlexRay communication cycle, as it can be the case, for instance, if legacy software is to be re-used. First, we provide solutions to verify the freshness constraints of the signals exchanged in the static segment, under the form of both simple non-schedulability tests and an exact analysis. Then we propose a heuristic to construct the communication schedule, which proved to be efficient in our experiments. Finally, we highlight some future work that should help us further optimize the configuration of FlexRay networks, be it in regard to hardware resource usage or dependability objectives.