No the loose sideplate do nothing to do with your problems.
THe problems is either a loose searspring or a "adjusted" sear or firingpin, this is also very much proved by the fact that the triggerpull is very light.
I belive the parts are adjusted and the searspring is likely ok, because on a normaly luger where the searspring is removed the triggerpull will still not be extremely light.
Best Regards HÃ?Â¥kan
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