Is a Jewish woman who files a "Shlom Bayit" (marital reconciliation) plea at the Rabbinical Court, for tactical reasons, and asks for maintenance, after her husband has filed her for divorce, likely to be awarded financial support?

Yes!The fact that a husband files his wife for divorce does not, in itself, take away or reduce her right to maintenance from him so long as they remain married. Her right to financial support from him will only be affected,while they remain married, if he manages to prove one of the grounds recognised under Jewish law for cancelling it, or reducing it.