So you want to use ORANGE, but you want ROOT output rather than HBOOK? You might find this Orange-root interface interesting.
If you use root then the general ZEUS C/C⁺⁺ analysis library I am building might also interest you.
I maintain an updated version of Oliver Gutsche's standalone version of zevis. If you want to use it check this page

Documentation of Electromagnetic shower shape variables implemented in phantom and orange by Matthew Forrest and me.