// OnPlayerRegister

ShowPlayerDialog( playerid, 99, DIALOG_STYLE_MSGBOX, "Intro", "1st Dialog About RolePlay.. Do you want to continue? ", "Yes", "No" );

// OnDialogResponse
public OnDialogResponse( playerid, dialogid, response, listitem, inputtext[ ] )
{
    switch( dialogid )
    {
        case 99:
        {
            if( !response ) return Kick( playerid ); // If 'No'
            if( response ) // If 'Yes'
            {
                ShowPlayerDialog( playerid, 99, DIALOG_STYLE_MSGBOX, "Intro", "1st About RolePlay .. ", "Close", "" );
                return 1;
            }
        }
        case 100:
        {
            if( response )
            {
                ShowPlayerDialog( playerid, 100, DIALOG_STYLE_MSGBOX, "Intro", "2nd Dialog About .. ", "Close", "" );
                return 1;
            }
        }
    }
    return 0; // "return 0;" If it's FilterScript
    // Else if it's GameMode "return 1;"
}