The second picture seems to show "half-size" ones, these are two different boards. The second one has obviously been modified to accept a standard DIN-rail main switch.
If you google "Federal Electric UK" you'll find plenty of pictures. Apparently they had a plant in Telford well into the mid-1990s when production was taken over by/renamed to Square D and then Schneider.
This is a UK-made StabLok:http://srselectrical.co.uk/image/cache/data/SRS%20Electrical/DSC00308-500x500.jpg
Later ones were already to European standards (this one being a B 32 A) and light grey instead of black:http://www.harbordelectrical.co.uk/...LECTRIC_MCB_HBNA-M9_TYPE1__32A_3_POL.JPG
Reports on the internet seem to indicate that the UK MCBs might not suffer from the same issues as the US-made 2-pole ones but partial or total bus meltdown appears to be very common.
And yes, there is an essential difference in the distribution systems used in the US and most of Europe. The majoritiy of European countries uses single-phase two-wire (derived from three-phase four-wire systems) or three-phase four-wire systems operating at nominal 230/400 V or back in the days of FPE/Federal Electric at 220/380 V on the continent and in Ireland and 240/415 V in the UK. Two-pole MCBs were essentially useless in Europe but three-pole ones fairly common, especially in Germany where even everyday loads such as domestic cookers are three-phase loads (usually two rings per phase and the third phase for the oven, all heating elements connected L - N).
FPE Germany (or another yet unknown branch) not only produced MCBs and enclosures though. Yesterday I rummaged through an old box with plugs and trailing sockets and stumbled across a big metal three-phase plug made of die-cast aluminium (15 A/380 V) with the FPE logo! Interestingly the only approval mark is ÖVE, i.e. either this specific type of connector was only standardised in Austria or it was made by a yet unknown Austrian branch of FPE.