The german bit comes from when Hk retro-fitted the a1 so that it actually worked

And since Hk was owned by BaE at the time, it's all British
Yup.
H&K were owned half and half by BAE and the British Government. (The German government bought them back in 2005 IIRC)
The mods were designed by BAE's engineers/designers and current soldiers. They were added to the SA80 family in the Nottingham RSOV factory, which is
now run by H&K, but wasn't at the time.
This notion that H&K
made the L85A2, or that the SA80A2s are German is complete nonsense. Its like saying all NATO countries in the 60's-80's used British tanks because their tanks used the NATO standardised gun, the British RO-L7 105mm gun.
[Take a deep breath Hubert, breathe!]
Ok, trying to get this fairly on topic -
WE have already released 2 'upgrade' parts. Bolt catch release and something else. Why?
Becasue from the reviews I've read, it seems that the BCR is one of the first things to brake, 2 people having them break as they
take the damned thing out of the box.
I think it'd be better to wait a few months before you take the plunge and buy it. That, and you never know, they may hopefully release LSW/AFV kits (I'm not keeping my hopes up, but a man can dream, right?)
MAGPUL - if it adds comfort, then go ahead. I'm all for people adding things to their weapons that, yano, make them
pleasant to use. AFGs? Go ahead. E/PMAGs? Yup. However, MAGPUL'ing up your gun so it's all 'tacticooooool', bolting on anything and everything? No. It just looks like a truck filled with MAGPUL gear exploded next to you. And I'll wager that some of the gear gets in the way of the other stuff...