So, 9 people booked from HUY-AMS-KRK last week, but the flight from HUY was cancelled, due to fog. After a LONG phone call we were rebooked out of MAN to MUN to KRK the following day, on LH.

We had to spend Ł75 each getting to Manchester on the train, spent Ł130 a room at the airport and then had to pay Ł75 in baggage fees, as my LTPE allowance was no use on LH.

We lost a night of out holiday, lost a night in a prepaid hotel, and the minibus booked for Krakow was cancelled and non refundable.

I approached KLM for EU261 compensation AND the incidental expenses, and was given the "beyond our control" cop out, and the expenses were "too remote" to be considered.

The sad thing is, that 5 of the party were with me in Asia earlier in the year, when KLM cancelled out flight back from Bangkok, stranding us in Hanoi, meaning we got rebooked out of Singapore 4 days later, and refused to pick up the costs of getting us from Hanoi to Singapore, the additional 3 nights in a hotel there, to wait for the flight back to AMS.

They have now refused to fly KL/AF again, not that this will bother the airlines, but it does absolutely stink.

You should have asked for the hotel in MAN, not the hotel in KRK. The first is covered under duty of care, the second is not.

​​​​Transport costs to MAN are probably not covered as it was a voluntary choice (perhaps not "common sense", but at least follows some sort of logic).

In my recent rebookings onto LH I have been given the free luggage allowance, so I would certainly ask again for that to be refunded.

Incidental costs like your transport in KRK will never be covered, that's for travel insurance.

No airline is ever liable for such incidentals at your destination (prepaid hotel, minibus). If you were required by the airline to travel out of MAN then you would have a good case for having the expenses incurred in getting to MAN covered; if instead this was a suggestion proposed/request made by your party it's less clear-cut.

That is why you should claim on your travel insurance - you cannot rely on any airline to make a gesture as a strategy for not taking out travel insurance. At the very least, check if there is some travel insurance component included in the credit card(s) you may have used to book any or all of this trip.

EU261 (or the UK equivalent - you flew out of a non EU country) will not work - it was weather, apparently. KLM has still the duty of care, but then indeed it should be their proposal to have you flying out of MAN and then the transfer costs, any additional hotel before the delayed departure and the like are for them. Not the costs you made for arrangements at the destination that could not be met. Same for the situation in Hanoi - that is, if you had a Hanoi-BKK-home ticket with them. Then they should pay additional nights in a hotel in Hanoi and see how they can bring you as soon as reasonably possible home from there. If you only had a BKK-home ticket with KLM, KLM is only liable for getting you out of BKK as soon as reasonably possible, and give you a hotel in BKK while waiting. If all flights were full and you accepted a solution flying from SIN, then indeed it is your own responsibility to come from Hanoi to SIN, since you were not in BKK. In case you had a BKK-home ticket a next time I simply would go to BKK from Hanoi as planned and have things solved from there, with them responsible for the hotel and so on.
Since you were are party of 9 that may have complicated things - how do they find a block of 9 open seats on the same flight so short in advance.

The rebooking out of Manchester and subsequent expenditure was KLMs suggestion, not mine, so the cost of getting there, and staying overnight to get a 6am flight has to be KLMs responsibility surely ?

Hotel: definitely (this is explicitly addressed in the Reg). Transport to Manchester: strictly speaking, the reg only explicitly anticipates the issue of arrival at an alternate airport rather than departure. However, I would expect that the ECJ would probably apply this by analogy in relation to alternate departure airport but I would not be surprised by KL rejecting this and forcing you to court to fight the point.

Honestly just go to MCOL

I tend to agree, but to play devil's advocate you accepted their suggestion when you could have chosen to stay at HUY (at their cost?) and get the next available flight from there.

They couldn't offer a Humberside option, in the ensuing few days.

After much to-ing and fro-ing I got a replay advising that the Ł61 spent on train fares getting me to Manchester airport would be refunded (and it was).