Hi and welcome,

All Focus have Central locking, but CL as said doesn't have remote, however in this case it sounds as if your central locking is not working if it's just opening the drivers door and nothing else, so I would be checking fuse number 63 (20A) in the passenger fuse box (Behind glovebox)

The high idling I would say is caused by the vacuum pipe as said, if it is this it will be letting in the extra air which is leading to the higher idle (air leak) I don't think there is anything wrong with the ISCV.

Martin