Help with hold open device

[cliffdropover1]

I am trying to repair a luger and the hold open device will not work. It will hold the toggle back if pressure is applied to the bottom of the magazine. If the mag is pulled even slightly, the toggle slams shut. I have checked the hold open spring and part and they seem ok. I have tried other magazines and while they work fine in other lugers I have, they won't work in this gun.
The gun has all mismatched parts and has been refinished. Perhaps this has caused the problem. Any help here is greatly appreciated.