Have to get married at a registry office before our wedding day

We are getting married in an un-licensed venue which means we have to get married legally at a registry office the day before our wedding and have a celebrant on the day of.

Im really worried because obviously my closest family (parents and siblings) and my partners parents and nan want to be there for the official wedding, which I get, but I really don’t want that part to be the main thing and take anything away from our wedding day itself. I know it is the REAL thing but I don’t want such a fuss to be made that when we have our ceremony at our beautiful venue & our celebrations, they don’t feel as special.

has anyone had to do this before? Can you explain what actually happens in the registry office? We don’t want to exchange rings or say anything too romantic, we just want it to be the official ‘signing the papers’ part.