API Backwards Compatibility

We are building a Bridge to ERP software program and trying to know backwards compatibility to version 2010 and earlier.  We built our program with the 2012 API as recommended by Solidworks.  However,  we wonder what issues we need to be aware of for running our program on earlier versions.  If anyone has experience with this,  we would like to know what to look for. 

SolidworksApi macros