You need to interface it with Insteon_ExtDevSupport_Support.vb found in the scripts directory. You will have to rename it to Insteon_ExtDevSupport.vb and modify the file for the EZIO8SA.
Good luck. Mine works well controlling the outputs but has no clue as to the status of the inputs. There is also a file I found on the Homeseer board called EZIO2X4 that looks interesting. I get similar results using it with slightly different results. If you solve the input status problem, Please let me know.