[Pfsm999]

It's Done !

Do :
./steam -command update -game left4dead2_demo

And when you finish to download all Windows File, TADAAAA :

Checking/Installing 'left 4 dead 2 demo linux dedicated server' version 1
79.53% ./left4dead2_demo\platform\tempid.txt
79.83% ./left4dead2_demo\bin\datacache_linux.so
80.16% ./left4dead2_demo\bin\dedicated_linux.so
81.90% ./left4dead2_demo\bin\engine_linux.so
82.18% ./left4dead2_demo\bin\filesystem_stdio_linux.so
82.57% ./left4dead2_demo\bin\libsteamvalidateuseridtic kets.so
82.63% ./left4dead2_demo\bin\libtier0_s.so
82.67% ./left4dead2_demo\bin\libvstdlib_s.so
83.27% ./left4dead2_demo\bin\materialsystem_linux.so
83.33% ./left4dead2_demo\bin\scenefilecache_linux.so
83.39% ./left4dead2_demo\bin\shaderapiempty_linux.so
83.53% ./left4dead2_demo\bin\soundemittersystem_linux. so
83.55% ./left4dead2_demo\bin\steam_api_linux.so
84.68% ./left4dead2_demo\bin\steamclient.so
85.04% ./left4dead2_demo\bin\studiorender_linux.so
85.09% ./left4dead2_demo\bin\tier0_linux.so
85.09% ./left4dead2_demo\bin\unitlib_linux.so
86.51% ./left4dead2_demo\bin\vphysics_linux.so
86.70% ./left4dead2_demo\bin\vscript_linux.so
86.80% ./left4dead2_demo\bin\vstdlib_linux.so
87.30% ./left4dead2_demo\left4dead2\bin\matchmaking_ds _linux.so
...

Yeah !

[panchoman]

thank you so much!