I got the same problem, I can not get a stopover in Z8 with my Z1-Z7 ticket.

If PTS are answering DC e-mails these days, I would fire off a quick e-mail asking them to confirm one way or the other the validity of the routing.

I had a similar issue doing LHR-KUL-HKK with stopover in KUL. I wanted F cash+ miles and the only option was LHR-BKK-KUL-BKK-HKG on TG which was a no goer with the ICC because of the backtrack. So instead the next time I phoned I just said I wanted to go from LHR-KUL in F then onto HKG again in F. Didn't mention routes or flights. Couple of agents gave me the "No availability" but I knew there was from the ANA tool.
On the third call got exactly what I wanted no mention of backtrack etc,etc. So my advice would be just tell them your starting point then your stopover point then your final destination and let them fill in the blanks. YMMV

:)

Would EUROPE-FRA-PEK-BKK-KTM-BKK-PEK-FRA-EUROPE be ok? I am guessing not but I need to ask at least :) Or does anything europe-asia-bangkok-ktm works? Yes I will be flying the entire route.

Europe - BKK (so) - KTM and vice versa is no problem provided you do the whole route. Even if you just want this as a cheap way to BKK it's worth going to KTM even for a couple of nights as it's an interesting place and not expensive. In my experience the BKK-KTM flights in C are great. You might experience problem routing via PEK and BKK as there are flights from PEK - KTM direct.

This could be two awards, namey Z1/Z8 and Z8/Z10

Apologies for being a bit of a novice but how do they decide which stopovers are allowable where you travel through a higher value zone than you end in?

For example:

LIS (z2) - LHR (z1) - HKG (z8) => z2-z8??
CPH (z2) - BKK (z7) Stopover - HKG (z8) => z2-z8??
LHR (z1) - BKK (z7) Stopover - KTM (z10) => z1-z10??

I just want to understand correctly so I can maximise the miles I have!

All of these were, and to best of my knowledge still are allowed. However, some recent posts in this thread suggest that matters are becoming a little more problematic in recent months. For example, some agents are more stringent than others, mixed-class redemption problems, F-issue for domestic flights in USA, married segment rules and so on. It is a long thread but by reading through much of it you should get a handle on the issues. My own feeling is that with the right agent and with sensible requests that are not obviously just designed to exploit the loopholes and rip BMI off then the agent will try to meet your needs. Avoid very complex routings where simpler ones are available and don't jump ship in BKK or SIN on z1/2-10 redemptions and hopefully everything will be ok.

This should be no problem.
I just did BUS-IST-BKK-KTM with an overnight in BKK in July.

I dont know about PEK though, but I dont see a reason it wouldnt be allowed, especially if there is no direct FRA-BKK available on your dates.

JFK-IST-FRA-BKK-USM (under 24 hours in FRA/IST) is that ok? I'm worried about the backtracking... this would be a valid z3-z7?

Well IST-FRA-BKK-USM is the second result on staralliance.com, which makes it more likely to work. However at the same time JFK-IST-FRA is the problem... is there no availability to FRA/VIE/MUC from JFK on your dates?

I think you can try it and see, but you might expect them to suggest a better connection in Europe.

this is a backtracking. they also have direct flight from IST to BKK.

hum, I was debating doing it as z3-z7 in First, with TK F to IST, no availability on the IST-BKK on the dates I was looking at... but then I realized that it's 2.5x instead of the 2x multiple I tought... I might do it as a z3-z8 in business, KTM is a place I want to visit...

I've gotten this to be a valid z3-z7 with bmi ICC

LGA-YYZ-NRT-ICN-BKK-USM, thinking of replacing USM with KTM and making it a z3-z10 for less miles (sub 24 hours stopovers in NRT/ICN)

I'm hoping to do a route such as the following using miles plus cash in business class:

GLA\EDI - FRA\ZRH\AMS - SIN (STOPOVER) - KL return

Will this be possible and how many miles and cash will it set me back for 2?

Thanks in advance.

FRA-LAX-AKL-CNS allowed?
 

Air New Zealand are the only * carrier going to Cairns, Australia. If I am lucky enough to find availability on all the three segments (FRA-LAX, LAX-AKL, AKL-CNS) would Diamond Club allow me to book it as a one-way from Europe 1 to Australia?
Thanks, ps