Thanks. This is very helpful.
Just checked that diagram. The previous guesstimation was not too far away from it.
The trigger has "U" shaped sear arm, the back arm of "U" facing the sear is narrower on the top so it does not touch the sear when trigger is at rest. When trigger is pushed, the back arm of "U" raises its position and gradually pushing the sear bar inward. Sear bar rotates around the sear screw and release the firing pin. The disconnecting mechanism looks same as Parabellum.
http://www.mek-schuetzen.de/Blueprin...ing_Pistol.png
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The trigger has no pivot. It's hard to see why it does not fall out.
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Never mind. Picture #11 tells why the trigger does not fall out.