No worries. Happy to help.
So, we tried waiting for the freeholder to intervene - since this it is what is required for the first two years, per the terms of our policies - but found him totally unresponsive. Our emails were routinely ignored and we even found that he was trying to sell the freehold, without notifying us, via auction. We instructed our solicitor to intervene on this and had the listing removed. Following this, we also decided to purchase the freehold from him, for a peppercorn, with his liabilities wiped clean, as a means of expediting matters. It sort of worked. That's a separate story, though.
On your property: presumably you received a policy document when you completed? I'd refer to this, but am fairly sure it will say that if the freeholder is proving unresponsive to your requests, you are within your rights to open insurance claims yourself, after two years, as leaseholders. As above, this is what we did after of being ignored by our freeholder, and, reluctantly, the insurer was forced to accept our claims. They tried to make contact with him, as part of a "dispute resolution" process, but, like us, found him completely unresponsive. This gave us some momentum, since we'd removed one stone-walling party from the process.
It sounds like you'd be in a position to submit claims now, if the policies are comparable. You're probably already doing this, but i'd suggest taking photos of everything (ensuring they are time-stamped), keeping record of all emails with the freeholder and insurers, which indicate negligence or stone-walling, and bringing in some contractors to give their views on the quality of the build. Also write to any body you can think of, such as ombudsmen, your MP, the insurer, flagging negligence across the parties. Ask your MP to write to them (they will). Ask your solicitor to write a letter to the freeholder threatening a personal summons (they will). Go through your policy pack and identify the time-line and wording for dispute resolutions/claims and pull together a letter that shows they are falling below their contracted standards. Also, go to the planning office of your council and ask to see the structural plans. Take photos/copies of these and share with the insurer, when the time is right. This will speed things up, but, as a warning, its a long, long process in the main.
Ours was complicated by our insurer going bust in 2019, but as a guide: the level-monitoring of properties, once claims are accepted, will usually last at least a year and a half, and then there are tenders for work and repair plans to be drawn up. Works on my property have only just started (despite my raising issue in December 2016 and formally submitting claims in October 2018). COVID has been a great excuse for further delays, too.
I'm not sure how big your development is, but it might be worth seeing about taking on the freehold. I know its probably the last thing to cross your mind at the moment, given the stress of his/her stonewalling and your determination to make them remedy the build, but it may be beneficial in the long run. Just think: no service costs, no ground rent, no issues when selling, because you will be compelled to disclose details to a prospective buyer, a 999 year lease, and absolute freedom to do as you please to your property, without some as*hole getting in the way.
Feel free to drop any other questions. Having lived through this nightmare, I feel obligated to help others avoid it!