craig

The adjusment is usually +/-3mm, the distance varies on system but HF410/HF510 you're look at 13.5mm distance between frame and sash (timber to timber), the keeper is roughly 8/10mm in height and the mushroom sits inside the keeper when locked.

Numpty was on his phone and couldn’t see them for looking at them and they’re grey. So it is clear I now need glasses. Still reckon to low or too much to the side, meaning a slight adjustment required.

I don't see any seals on the pictures supplied but I do see the gearing mechanism and in particular the mushroom pin on the first picture. It "may" be that the sash is needing adjusted in width/height as the pin is to close to the locking keep.

Context, would need to see a picture of what you are referring to, as @markc as said, is it actual glazing bars (astragals/georgian feature bars) or is it the glazing beads that retain the glass. Glazing beads can be internal and external, it's a lot to do with the system in used but it would be unusual for them to be inside and outside on the same unit. Where the sides coupled (i.e. seperate to the french doors)? If yes, then side windows would "appear" to be on the wrong way around.

You can use a simpler method. All the integrated one is doing, is effectively turning a stopper to prevent the window going into the turn position and allowing tilt only. a simpler method is using a screw at the relevant point on the mushroom pin, preventing the pin going in the direction of turn/tilt.

Where did you get the door from? What is the make/model? Do you have any pictures?

Solar glass is a minefield of different options/coatings etc. I try to avoid it if and when possible (which isn't always the case) but options exist. Most glazing suppliers will offer solar coatings but not all do (such as Everest). Why do I avoid? Light transmission, Solar coatings really darken up the glazing units and I personally don't like the look. I'd much rather go for external shading components, such as trees, brise soleil, canopies etc.

It’s unlikely that they have, unfortunately, it will be within acceptable tolerances. You’ll need to ask what those are and whether they accept any liability. I suspect not. Don’t try and cut it, it’ll end up in disaster.

Old cottage you say, do you have any wall vents?

What Nick said.

It's about how it is worded, it is likely to be part of the wording for renovation replacement but if you could paste the entire wording for context, that would help. Generally speaking though, on a new build, it's inputting the windows, fixing method, PU foam, airtightness tapes and externals left to others.

Whats your location @Talaidh?

No, I leave that to those trained and qualified to install and maintain the products. Everyone “thinks” it’s easy to do but it’s far from easy.

We’ll agree to disagree.

We both could post examples all day, don’t deny it but it is a trade but I do agree that there is a substantial amount of unskilled installers.