Nooto

I use Sculptris as my main modeling tool for mesh for second life, i can tell right away your triangle count for your model is far too high for second life. You can make massive reductions to your models triangle count in sculptris with the Reduce Brush alone.Even after that you can still make more reductions to your model in Blender with a modifier called Decimate. These are just a few things you can do to make your models Second life import an easy one.