The PSU supplied with your unit in the UK may have come with a full set of adapter plates, but are you sure every territory receives the same all-encompassing set?
I wouldn't be so certain based on my experience of receiving review kit directly from overseas distributors...
but I think the ultimate responsibility lies with the manufacturer.
Ultimately, yes, I'd agree... but I don't think it unreasonable at all to use the local distributor as the first point of customer support. It neatly avoids problems with languages, time zones, international shipping, customs and taxes, and is legitimately justifying some of the profit margin distributors take!
In the UK, the ASM distributor is Source Distribution and I've always found them to be extremely helpful and easy to deal with.
I note the psu rating for the deluxe model states it must supply more than 2A, which implies a 1A rating on the standard model might be a little tight.