I want to play this locally, I can't see the other lobby in both computers, i've tried many things but only tunngle worked for me but you cannot use tunngle offline, I want to play locally LAN.

How to setup the SSE, It requires the original steam_api file, How ?may i ask
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this is the one you want

As you can see under the last pic, it's highlighted in red that this RELEASE of the GAME also includes the former DLCs and content.

N SHIET