I've made some ladders on my first map, but they turn out invisible ingame...I've set differant materials on them, but nothing works.

You actually create your ladder with the ladder textures witch they all have the "{" symbole in them. Make your ladder and ctrl+T on it and set its render mode to solid and FX amount to 225. Then create a block same size as the ladder but place it on top of the ladder and make the texture the AAATRIGGER then make that a "func_ladder" That shoudl work

the "func_ladder" is just a climbable entitie
that you can't see
so you have to build the visible ladder behind the "func_ladder" entitie
the ladder texture, in fact, can be anything
with ladders
you need to objects
the ladder brush or block
and the "func_ladder" entitie
the "func_ladder" entitie must be in front of the brush/block that you use for the visible ladder

Alright, now I know. Thanks guys