Please Reply I can't use the Long Jump too, and it's the same problem When I press duck+Jump nothing happens...
and I think it is the problem with CS 1.6 Update... because they have removed Long Jump and the plugin using the default cs 1.6 Long JUMP...
as this PLUGIN says :[
https://forums.alliedmods.net/showthread.php?t=108382]
BTW CSDM Version: (CSDM 2.1.3d KWo)