Your developer has breached the contract ex art 1124 of the civil code because he has delivered substatially later than what was specified. You can hold on to this.
Although there must be some clause that specifies that in case of them breaching the contract you are entitled to obtain back your moneis (stage deposit) or else complete but with some kind of compensation. If this clause exists then you could have your money back but developers will be rather adamant about it and probably litigation will be necessary to enforce it unless you reach some agreement by which you lose all or part of your deposit but that would as If it were YOU actually who were breaching the contract and not them. I’m afraid there is no easy way out.
Normally there are compensation clauses that state that for each day that goes by the developer has to pay for example 50 euros for each day they deliver the property late, providing your lawyer managed to include them in the contract which often is quite hard.
It’s ok if the contract states they can change things for legal reasons or for technical reasons but it musn’t say they can change things for economic or commercial reasons.
Not having read your contract I think litigation will have to be the way out in your case. But I must add it’s not very professional on my part to give legal advice in a case like yours without having read your contract. So far your lawyers seem to be acting professionally.
No Consumer Law it’s hard to implement and generally involves litigation but it can be used as a threat against the developer if the breach is clear. My post was just stating that they cannot include a swimming pool in the publicity and brochures and then not build it. It’s contractually binding for them If the swimming pool appears in brochures, promotional videos, computer simulations, plans, sales office with scale model of the whole development etc…