Deriving tax rate from natural account

We are changing the tax set up from STCC (from upgrade) to Regime Determination Set.  The tax engine is working.  Now we are trying to get the tax rate to derive from natural account. It seems like tax deriving from the set up in General Ledger is not working. We have tried to define new rule using tax determination factor set and tax condition sets.  When creating transaction in Receivables we don’t get the rule to run. Is it possible that the tax engine will update or have the tax engine already run when we are changing natural account in