Famicom 4PLAY issue

[alexgame8818]

Hi~Thank you again for your great project:)
But I'm stuck again on building a Famicom extend port only RetroBlue.
Lasted Version 24.04,Japan AVFamicom console.

I connected all 13 cables from DB15 and made IO33 to V3.3 as well, but in 4play game it doesn't work.

In Multitap Config, if I pick Alt it even doesn't work in any game.
So I choose Dual, it's OK for normal 1-2play games, but in 4play games, 1st. controller wil be 3P, and 2nd. controller will be 4P,and this time RetroBlue cant allow any more controller to be connected.

In earlier firmware,I remember BlueRetro will not refuse more than 2 controller connecting.

I know P1D0 is not in extend port,but like HORI 4PLAY,they made a P1D0 signal from calculating P2D0.
I think it should be very easy for RetroBlue to make it:)
So is there anything I missed? I checked cables and chips several times.