Cracks in the screed. Problematic?

Why? What problem do you see there?

The screed standard states clearly and explicitly that the spacer strip must be in place. Also in the corners. If the spacer strip had been cut in the corner before the screed was installed, the adjoining (continuing) piece had then been set at a right angle and the spacer strips secured against slipping, there would have been a sharp corner formation there as well.

That is what the theorist says.

What is not okay, no matter what some shouted into the room, is the rounding in one of the corners.

Just lay tiles over it, please do not take this answer seriously!

That is common practice. If you find screed layers who create 90-degree angles, then carry them on your hands.

We want to provide technical information in this forum. And not on the basis of speculation, half-knowledge, and amateur handyman knowledge. For this, we must, if the responsibility of the questioner is not to be taken lightly, keep the situation before the applicable technical rules in mind. Specifically because careless statements, which the questioner then takes seriously, may prevent them from legitimately complaining about or reporting to the contractor a technically improper condition that could later cost them money (out of their own pocket) or leave them with a trade that does not comply with the technical rules. This is also not about "nitpicking"! Certainly, there are craftsmen who turn a blind eye and conceal aspects in need of correction with their trade. However, this forum, in which we operate, is intended to offer usable information to the questioner. --------------------------- I could, again addressed to "Onik900," neither from the text nor the photos discern whether, on the one hand, it is a heated screed or not and, on the other hand, whether the movement joint (and it will be such due to the type of construction) is even necessary and furthermore, whether it (and this would then be mandatory) runs in a straight line. Perhaps you should make a brief comment on this in order to be able to assess the process safely. Regards: KlaRa

Topic rounded corners
The criticism is directed less at the screed layer and more at the heating engineer (in the case of heated screed). The edge insulation strip is installed by him when laying the insulation/floor heating.
I have known screed layers as purely crew workers. Quickly in and just as quickly out and off to the next. Accordingly, the price for such a heated screed is also correspondingly low; it is one of the (financially) smallest trades on the construction site. Who checks any corners there and repairs them?!

: The installation of edge strips clearly falls under the trade "screed work" and is mentioned in the various screed standards, the listing of which I prefer to omit. Furthermore, in my entire professional practice, I have never seen a tender where the setting of the screed with edge strips is left to an external trade. No, that assumption is not correct! "Quick in and quick out" may, as I noted earlier, be the approach of screed crews in one case or another. But here we are talking about technical rules. And further: The technical regulations cannot be circumvented by price. This remark alone seems odd! Who rectifies defects? Always the trade responsible for the rule violation. The execution can (and this is the practice) be taken over by the following trade (which would be the floor layer here) after coordination with the responsible preceding trade and with cost acceptance. And who has the control? Well, that is quite obviously self-explanatory.

Moreover, in my entire professional experience, I have never seen a tender where the installation of the screed with edge strips is assigned to an external trade. No, the assumption is not correct!

I only know it this way: the heating engineer installs the edge strips. With the tack system, the edge strips are installed first – and in practice, this is always done by the heating engineer. Tender or not. Theory or not.
And it was the same here. Want to bet?
In practice, I have never seen in a single-family house that the screed installer comes first, sets the separating strips, and then leaves again. The screed installer comes when he installs the screed. Before and after that, he is not there (at most for moisture measurement, although this is better done by the floor layer).