Sorry to hear about the job but something else will happen and it will be good.
I will say that if you think the HR department was conspiring against you to schedule construction and not answer their phones, you are vastly over estimating the organisational competence of most UK businesses. Most companies I've been involved with can barely order paper towels correctly, much less organise such a crafty set of obstructions.
No, I don't think the HR was conspiring against me at all.
I think they were out to lunch, either figuratively or literally. The level of incompetence in that particular larger organization is legendary. That they didn't supply direct contact info (or names) or provide info on the detours necessary to access the interview site kind of reinforces that, really. (No, really. I can see them on the phone - hey, we've got Ms. NanD coming in today. Quick, throw up a bunch of fences around the walkways to the building, tear out the concrete, and lock the doors!)
What I think may be the case, and I know this happens very often in the industry in question, is that they already had someone from either inside or outside the org that they wanted to hire (someone's friend or relative). The department still has to interview the requisite number of bodies to make sure they comply with "open recruitment" regulations, but they have already selected their candidate. So I had no chance from the start. There were to be no second interviews, apparently, so it was a one-time shot at geting it. If there was any chance at all.
Who knows? They may have wanted someone much younger. Or with a different set of skills. Or who was not a foreigner. Or... there could be an endless list of "what if's" - and I'll never know because they don't do feedback. Or the 7 minutes late could have killed my interview from the start. Which is annoying as I was there fifteen minutes early, as is my usual MO. Again, no way to know and a set of blisters for my trouble.
Edit: Ok, well, blisters and a chance to practice interviewing. I thought the actual meeting went quite well - better than my "usual" interviews, which I tend to not do well in.