I created a shorter version of this post here:

https://community.eurail.com/ask-a-question-40/arghhh-i-think-i-m-in-trouble-with-home-country-travel-rules-1666?postid=6561#post6561

...as i thought this one had been deleted (it was on hold for moderation). Apologies for the confusion

Hallo, ja sie haben sich bestimmt verrechnet.

Day 1: this is 2 (zwei) trips IN DE on same travelday and thus not allowed. Visit this city of sin, where Ive worked too many years later on, its not really wanting tourists anyway. The discount for the NJ on a pass is also only about 15 eur/ride, in whatever class. Board this NJ in somewhere along RheinRuhr. leave home early enough to cater for the endless delays on DB or to enjoy the delights of the most neglected big city HBF in Germany; Duisburg! However, as you say you go with kids I really dont know how that will count for the supplements.

Maybe you could do if this is allowed: go on a family Münsterland tageskarte via Gronau/Enschede=start IRpass?? to AMS, which does not cost too much extra, but then you still have a TRANSIT and not a start trip on the NJ across DE.

In fact as you also want to use another NJ-I think that booking advance and hopefully on a not too busy day will cost less in fares as travelday (1 of 4,about 45-50 eur)+surcharge. I have seen recently new prices for NJ when using a railpass, but forgot where, so I cannot give the link right now. But then you mention another NJ trip.

IF you use the slower IT local=regionale trains, Genoa-Ventimiglia=border, cost not that much and for the short FR part there are daypasses for this area.

Then only the long final trip home counts, and you will be faced with the usual problems of booking french state/strike railway TGV. I see you mention Est station, so that means not the Thalys. These INTernational trips on TGV (I guess via Saarbrucken or FRA?) cannot be booked online, but your friendly DB schalter in the new shiny Münster HBF can do it. There will again be a hefty surcharge though. More as you would spend in the 1 eur shop in that shiny station, where all things cost 1,10!

All in all: going on an InterRailpass does not look to me as best solution for this. You forgot that these overnighttrains still cost a lot of supplement to pay as do french TGV. Really sorry to break the glass, but better face reality now as later.

Assuming you are german and this is a bit beyond my scope of knowledge: visit the german train-lovers forum drehscheibe-online, make an account, and post question with suggestions as many dedicated and up to the minute knowledge of about all alternatives and ways to do and maybe even cut the price for traintravel. Use ´allgemein´ as subforum. Succes with it! In fact quite a few of those friendly DB-schalter even visit it and can even look for details in their computers.

Ok thanks, i will need to figure out another way to travel. I don't actually want to go to Amsterdam by the way, it's just the easiest route. I also don't want to go to Munich, but there's no other night trains that take the right routes. I think the train services just aren't good enough for such specific travel requirements. 

You could take a day train from Münster to München. And then board in München on the nighttrain to Milan (all this is one travel day). For train to Genova you need a new travel day or you buy a cheep regional ticket.

If you want to take the nighttrain to munich, you can enter to this nighttrain in Düsseldorf or Köln. Without using the inbound but only the outbound journey, because you don’t leave germany. The nighttrain to munich goes till Innsbruck. You could stay in Innsbruck for the day and then take a Railjet to Salzburg (actually via Germany → but it is a “Korridorzug” this means it is like it would not leave Austria). 

Or you take of the same nighttrain (from Amsterdam/Düsseldorf/Köln) the part to Wien/Vienna. Stay there a day and then take in Vienna the nighttrain to Milano (this arrives at the same time in Milan as the nighttrain from Munich).

I'm so sorry for causing confusion, as i started yet threads on the same topic, thinking my first one had been deleted. And in getting great replied on both topics, both with different solutions, so i didn't want to delete either of them!

Thank you Angelo, you've been super helpful in both threads! The korridorzug thing is new to me, very useful to know!

Following up on the Korridorzug idea, would that mean the night jet train between Amsterdam and Austria, via Germany, wouldn’t count as travel in my home country (as I wouldn’t actually set foot in Germany)?

example:

No, it doesn't work like that. That would count as travel in your country of residence.

The corridor train mentioned is a special case: for the tariff, that trains stays in Austria and that's why it doesn't count as travel in your country of residence.

Thanks for confirming. In that case, the solution in my parallel thread seems to be the winner. 
 

apologies to everyone for my complaining and whining at the beginning. I was rather stressed at having committed to a holiday without realising the implications of travel restrictions!
 

I’ll create a new thread soon to check a few other things. Have a good day everyone.

@bluemanontelly 

Nightjet self have special offers like Privatabteil Liegewagen (Private Couchette Compartment) from 199€ (Ticket and reservation) depending on how many traveltogether this is often the beter value instead of Interrailday + Reservations that can be quite high (For example one berth in a 4pers Couchette for 44€ ) Maybe it´s a option for you and select with the saved travelday  a new stop along the Route ;)

These Specialfares are not exchangeable or refundable :/