Hi d165,
You may need to email me so I can get the info to understand what is going on, however as a firm that Contracts Administrates over $40mil of Strata Refurbishment each year I can say that if the contract has been set up correctly the repair responsibility is on the builder. Any replacement of windows will cause some damage in the process of removing the old windows, most times the damage is repaired as part of the works.
With the information you have provided I can’t help much more, if you need further info send me an email.
Best regards.