How to recompose on a Sony A37?

I was a Nikon user for four years and I like it better than the Canon I occasionally borrowed from a friend. But, because of financial needs I have sold my camera. Last week, a friend gave me a Sony A37 plus two lenses (18-135 SAM and 55-300SAM). I like the camera because of its interface. However, I find it weak on the one I used most often, the selecting the focus point because it takes several steps for me to do it. What I normally do (using the Nikon) was to choose one specific focus point, then recompose. However in the A37, when I recompose, the focus does not lock with my original focus point even if I would press the AE lock button. While in the Nikon, I don't even have to press the AE button. I can halfpress then move the focus point easily, then click when I find it OK. That enables me to track my subjects especially when it is a dancer or a bird. Any advice please. Thanks! ---Vernz