I just bought a 2012 Focus estate - got it at a decent price but of course there are a few niggles.

The nearside rear light cluster (body section) has a standard bulb in it (for the lights) whereas the nearside boot door section has an LED strip, as do both sections on the offside. 

I am assuming that the rear lights on the Titanium models came with LED strips whereas models lower down the range had bulbs? I'm thinking at some time in the past someone has replaced the nearside body section cluster with one from a non-titanium model. Does this sound likely? Or are the LED sections non standard?

You are right. High spec models had LED rear lights, lower models had bulbs. Someone has changed one of the rear lights and used an incorrect part. I think that the LED rear lights were paired with projector headlights incorporating LED front running lights, do you have those?

The Titanium X got the projectors with DRL's.  Standard Titanium just has conventional reflectors at the front, but LED strips on the rear.  As you say, someone's fitted a poverty Zetec cluster instead of the Titanium one.  

Thanks guys. Tom is correct, no projectors but LED strips at the rear, well, three quarters them anyway! I'll have a look out from a replacement. Presumably I'm not breaking any laws in the meantime, just looking a bit lopsided!

Just a thought Tom, or anyone who might know, could I fit Titanium X headlights to my Titanium and get the projectors and DRLs, or does it require re-programming to make the car speak to the lights?

It's possible but a lot more hassle than its worth in all honesty.  You'd need the light clusters, washers, levellers, some extra wiring and then have to program it in.  There are a lot of complaints about the light output of the xenon's on here as well, you'd be best off just upgrading the bulbs in your reflector lights imo.