Sorry, but your english is hard to understand. I will try and answer your questions the way I read them.
To add an entity simply press the 'Quake2 Entities' button which should be located to the top left. The button looks like a blue cube. When you press it you should get a list over all the entities divided into several sub-folders.
Hope that helped and the best of luck with your mapping. More mappers are always welcome :-)
Instead of using .ent files, we've decided that using Quake2 Equivilents is the way to go.
Whereever you want a certain Action Quake2 weapon or ammo, just place the Q2 Equivilent from the list below:
* Shotgun = M3 Super90 AssaultShotgun
* Machinegun = MP5/10 SubMachinegun
* Rocketlauncher = Handcannon
* Chaingun = Sniper Rifle
* Grenades = M26 Fragmentation Grenade
* BFG10K = M4 Assault Rifle
Here is the ammo list:
* Box o' bullets = Pistol clip
* Box o' shells = 7 pack of shells
* Box o' rockets = Machinegun Magazine
* Box o' slugs (railgun) = Sniper ammo
* Box o' cells = M4 ammo
Knives can't be placed. You start with one and the only way to get more is by killing people That's it!
You need not worry about items such as the kevlar vest, they spawn automatically in respawn sites like in CTF.
For doors to work like real doors, make them rotating_door, toggle, and wait -1 so they will stay open/closed.
New Info! Placing a rail gun in your map will appear as an extra handgun now! Akimbo without bloodshed. ;-)