[Dragokas]

Where can I send a set of bug reports directly to developers,

omitting million of standard questions from steam customer support staff,

like they always asking to understand whether I am a full user, like "reboot your PC" e.t.c.?

[myljach]

I think you mean avoid to send report like here --- https://steamcommunity.com/app/550/d...5820077942910/ most close what you may get is to try contact in steam Raymann1103 direct, because he may send your request to Valve guy who made that last stand upgrade. I understand that friends of steam L4D2 moderator, Raymann1103 was create that Last stand, and Rayman contact Valve guy, if i remeber Kerry or Garry to compile it to source engine, something like that.

[Dragokas]

That should be helpful. Thank you.
I'll try to prepare clear report of long time living bugs for them.