[Skimmer]

Well, i can script for you. First of all create a variable top of your script.

pawn Код:

new myGate; // Top of the script

Then create an object below OnGameModeInit(). Here's an example.

pawn Код:

myGate = CreateObject(974, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0);

0.0 is the coordinat from x, y, z, rX, rY, rZ Position. You can change it.
CreateObject()
Then go to OnPlayerCommandText(), we'll create a command.

pawn Код:

if (strcmp("/open", cmdtext, true, 10) == 0)
{
    MoveObject(myGate, 1.0, 1.0, 1.0, 3.0);
    return 1;
}

We created /open command, it opens the gate. 1.0 is the new x, y, z position. Like i said you can change it. 3.0 = Speed. 3 Seconds.
Here's /close command

pawn Код:

if (strcmp("/close", cmdtext, true, 10) == 0)
{
    MoveObject(myGate, 0.0, 0.0, 0.0, 3.0);
    return 1;
}

0.0 is the old x, y, z Position, you know.