Not such a serious case, but I have also experience of the Commission on 2 counts.
First was the anti-dumping duty and quota imposed on footwear in the late 90s.
Ironically UK manufacturing had been decimated through the late 80s and early 90s as Spain and Portugal joined the EEC.To survive quite a few UK businesses look ed to import and invested lots of time and money in setting up a supply chain in the Far East.
Only for the EU to bring in measures to protect the competitors that had been the main accelerant to the UK closures in the first place.
A double-whammy for the UK companies involved and for 20 years now the UK punter has paid inflated prices for footwear.
The Uk Government voted against back in the late 90s and have done so each time these measures have come up for review.
Clarks have also won a case in the ECJ who found the anti-dumping measures were illegal. They are still in place.
Second was when I held some shares in British Airways also back in the 90s. BA along with other EU airlines took the French Govt and Air France to court for illegal state aid.
They won - it was a court procedure over several years, but the ECJ found in their favour and Air France were directed to repay around 2 Billion Francs back.
A slight of hand from Commissioner Kinnock got them off the hook.