If there are not enough generations in your family tree it will disable the larger charts. Try starting with a name higher or lower in the ancestry depending on the type of chart you are generating (descendant or ancestor)
I said I had 10 generations. How many does it need to give me a choice of 7 generations showing both parents? It's never shown more than 7 and I've generated many different charts with more than 7 gen's. I bought a $1,000 large format printer to print these. I'd like to buy two more tree sites to print more charts but I'm holding off because of the problems.