LNK457DG Power supply with dimmer,LED flash?

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Hi!I have a question about the LNK457DG,i make a dimmable Power supply Reference the RDK-251,but i replace D4 to 1N4148 and VR2 to 20V Zener,D6 to 1N4007,D2 to ES2J,when i frist power up it,the LED flash.at first i replace C6 to 220nF
and R10,R11 to 300R,R7,R8 to 22R,C3 to 200nF for increase TRIAC holding current.power it again,but the LED still flash,I began to suspect that the transformer magnetic saturation,so i connect the 1.2R Resistance at the LNK457DG S and GND,i see the waveform but have no saturation and the peak current about 500ma.but i Do not worry,so i remake the transformer use a EE19 core,the transformer Leakage induction is 25uH
,but after replace it still flash.i have no idea.so i connect PI to look for help

at last my dimmer is CLIPSAL 32E450LM 450W