Jevery
The reason Normell says you should add malt instead of sugar is it gives you more body, mouthfeel and flavour, etc, and a slightly lower alcohol, as the unfermentables are the things that add body. Maybe pick up a pack or 2 of the Coopers brew enhancer's or whatever they are called. If you dont feel like doing that, 1kg of sugar will be sufficient. And try not to follow the kit instructions in regards to temps, ferment it at about 20C or so, even ambient temp should be fine at this time of year. The warmer you ferment it, the less likely it is to turn out well. The kit yeasts should ferment down to 18C or maybe even a touch less. Good luck with it, hope it turns out great
All the best
Trent