The only option is to covert files from SW2014 to parasolid, iges, step, etc. format and then open in SW2010. There is no other way and these converted files will open up as dumb bodies with no features.
You can go from 2010 to 2014 & keep all of the features & relations but you can't go back to 2010 once you've saved it in 2014. The only way to go from 2014 to 2010 would be to save as a step or parasolids file & then open that in 2010 but you would then be working with an imported model with no features.