I suppose its worth pointing out that the majority of caravanners who don't look at websites such as this probabley have little idea what 'noseweight' is. They don't check it, they just use their common sense. Its obvious when you load a car or a caravan that you should distribute the weight evenly & its also obvious when a car/caravan outfit is badly loaded or badly matched, you can see it with your own eyes. If it looks wrong, then it probabley is.
The 75kg on your trailer refers to the max allowable noseweight. I guess you wern't running at anything like that weight because presumabley you used your judgement when loading the trailer.
& so it is with your caravan, it is well within the capability of your car(max tow 1200kg I think)& I doubt you will be loading caravan to anything like its' max 900kg. It is difficult to weight caravan noseweight accurately, anyway. caravan must be level on level ground & best way to check is with piece of wood in hitch on bathroom scales. The telescopic noseweight checkers are often inaccurate. They give you a rough idea tho, which is all you need.
The static nose weight will be completly different from the dynamic noseweight, the actual noseweight of your van will be much lighter and indeed much heavier during the course of your journey.... a couple of Kg out will not make or break the towing experience, all weights will have an in built safety factor to eliminate idiots from the equation, saying all of that I spent ages getting mine as close to correct the first time I towed and it was great, between sites i wasnt so careful and I could tell the difference, a bit less stable, the lesson I learnt was take your time packing and go for the nose weight that you decide upon. Why not try a couple of the weights suggested on here? One may well feel better than the other and as TENTZ suggested many dont even know what it is!
Good Luck, it isnt as hard as it seems!