Aqui te dejo un ejemplo de codigo no utilizo zconnection:
Código Delphi
[-]procedure Tfrm_reg_tip_demo.conectabd();
var
MyIniFile : TIniFile;
BBDDhost,BBDDName : String;
password, usuario : String;
begin
MyIniFile := TIniFile.Create(ExtractFilePath(ParamStr(0))+'conexion.ini');
Try
BBDDhost:=MyIniFile.ReadString('BBDD','host','');
BBDDName:=MyIniFile.ReadString('BBDD','BD','');
Usuario :=MyIniFile.ReadString('BBDD','Usuario','');
Password:= MyIniFile.ReadString('BBDD','Password','');
PQConnection1.HostName:=BBDDhost;
PQConnection1.DatabaseName:=BBDDName;
PQConnection1.UserName:=Usuario;
PQConnection1.Password:=Password;
Finally
MyIniFile.Free;
End;
end;