Help, leaking from outside.

[E.F]

It's not easy when you're not on site but feel the same even though I'm here so hard to know. We'll continue tomorrow. Thank you all for your tips and ideas!

 

[janusz_w]

...
I think it might be between the plates/sheets. You can see in the pictures. Or what do you say?

I've had similar issues (though not as extensive, luckily). The window settled, and the window sill slipped out of place, just a little. But it was enough that when it was very windy, water came in and got under the parquet floor beneath the window on the inside. And we wondered why the floor looked like someone had spilled water there or left the window open when it rained. But it was from underneath.
So it is very likely that it's those gaps between the plates, visible in your pictures #27, that are causing trouble. Especially if the window faces west/south, that's usually where the wind comes from.

 

[E.F]

That's exactly where we believe the problem is. Surely many others have the same issue due to the location, wind, and rain. I have spoken with someone who works with metal sheet who will come and take a look at it.

 

[Kickan42]

there's probably no insurance company that covers the cost of water entering from the outside. They usually disclaim themselves from that...

then the chances of dealing with the company that installed the windows are probably greater.

I also don't think any insurance company covers this. I had to tear down my glass veranda and the terrace on top because water (rain) had apparently seeped into the floor/ceiling over a long period, resulting in all the timber rotting :/