1996 Escort Door issues - Ohgr
I've got an escort as above, in which if you lock the passenger side door and then unlock it from the outside and try and open it the door won't open. If you open it from the inside its fine. If you also unlock it from the inside and open it from the outside its fine as well.

Any ideas ?!

Its not got central locking.
1996 Escort Door issues - Screwloose

There's a problem with the linkage between the lock and the door catch.
1996 Escort Door issues - Ohgr
yeah I guessed that, thing is if you take the door card out you can see eveything moving pretty much as you'd expect.

I wonder if one of the cables isn't taut enough
1996 Escort Door issues - Screwloose

Try some WD-40 on the levers of the door catch. Three screws drop the catch out; take it right off and operate it manually to see the problem more clearly.

Isn't it a bit of snap-in bent wire between the outer lock and the catch. Someone forced it in the past?
1996 Escort Door issues - Saltrampen
Sometimes the Lock barrel has a lug which connects to and moves the cable or rod, if the lug is worn or has slipped, the movement is not enough to shift the rod / cable.
Try undoing Door card and pulling the cable/rod manually from the lock, if it moves then either the cable/rod is slack or the movement from the barrel is not enough. Chances are one of these may need replacing or repairing.