i've started to create custom maps....
i'm making a map on a field with a ton of bunkers tanks and things like that...but i've runned into following problems...

1: i can go through the models i use ingame...
2: if i make a entity it becomes invisible...

hope this is known problems...

1. Models dont have a clipping hull, so you have to clip your models manually. Most models already has a cliping made for them, search for Waldos model_zoo.zip on this board and look in it.

2. Some entities are invisible. Which one are talking about? Whats you rendering settings? My guess is that you are using render_mode: texture and fx_amount:0 ... try using 255 instead or swap to render_mode: normal

yeah pay attention to kehldon.

When you have trouble with an entity you MUST give us the entity name or what effect you need an entity for, otherwise we can't help.

i'm trying to make a ladder...if i use func_ladder then the ladder become invisible...the models i'm trying to use is the tiger.mdl
and kingtiger.mdl...

The func_ladder is invisible. It sits in front of a standard brush that "looks" like the ladder, so that when you go to climb the "ladder" you are actually using the func_ladder right in front of it.

See this quick tutorial here:
http://collective.valve-erc.com/index.php?ent=func_ladder

As for models, good tutorial with all you need to know right here:

http://www.mardymouse.co.uk/modules.php?name=Content&pa=showpage&pid=34

almost forgotten...why are there no trancparrency on my textures?

To make a texture on a brush transparent:
Use a texture that begins with "{" (eg {vent)
Right click on a brush, make it an entity. Make it a func_wall.

Give the func_wall the following properties:
Render mode: Solid
Render Amount: 255.