[Dx4win] Polling rate

[Radivoj Kar, F6GNZ]

I have found a way to interface/synchronize  my SDR Console (for RX) and FT1000MP controlled by DX4WIN via microham Keyer/Router (for TX) . For this I am using virtual port pair creator VSPManager  from K5FR and RigSync program from W2RF.
The problem I am experiencing now is that it takes some delay between selecting frequency/mode on the SDR and having it refelected on the FT1000MP. To improve the situation I wish to reduce polling rates. Currrently in DX4WIN polling  time is 500ms.

What could be a minimum polling rate that would not impair the DX4WIN/FT1000MP operation??
Also, FT1000MP CAT baud rate is set to 4800. How high could be increased to?

73, Radi F6GNZ