That the architect’s planning did not please you, you have already mentioned several times. Nevertheless, you signed a contract and a working plan. The price and schedule are based on this. Any change (regardless of who is "at fault") costs money and takes time. This is then borne by the client, which in this case is you. The windows deviate from the original plan, so the delay is also your fault. That you possibly wanted it this way from the start does not matter, since it was not commissioned so far. I can very well understand your frustration and also that as a layperson you cannot have full insight into all details. Nevertheless, what counts first is what was contractually agreed. Otherwise, anyone could do whatever they wanted at the construction site. Since you have now entrusted the matter to your lawyer for some time, you are certainly entitled to do so. But you surely do not actually expect that the "defendant" will now accommodate you in any way. He will try to complete his work as quickly and contractually as possible so that he can close this losing business.
I have the feeling that you rushed into the endeavor a bit too quickly in the beginning. Either it was the "time pressure" or the euphoria, I don’t know. The contractor apparently did not sufficiently point out all conditions to you or you talked past each other. I do not want to judge that and as a customer one can naturally find this reprehensible. But: Ultimately, you still decide when and how you enter into contracts with whom. If you signed something that was not in your interest, then you are not innocent in this either. If you, to put it provocatively, did not understand the content, then at that point you should have consulted a construction supervisor/expert/architect. Of course, the builder can and may do this too, but he is not necessarily obliged to discuss the basics of landscape planning, statics, etc. with you. If, on the other hand, you already knew exactly that the plans did not correspond to your ideas (window heights), then I wonder how anyone in the world could sign it voluntarily.
Ignorance unfortunately does not protect against punishment.
The issue with the height of the house is not for me to assess here and it may well be that you are acting legally correctly in this case. All other matters, however, appear to me to be very much exaggerated and an attempt to badmouth a company here at all costs.