thank you very much for your rapid answer; I'll try to be more precise attaching the pics 2 edges of the experimental data
and the picture of one of the two set of experimental data (the other one is still the same)
after the multi-edge fit. Also I've attached the .apj. 
What I'd like to ask is : is there a particular procedure to make multi-edge refinement with
artemis?
just because maybe i'm using a wrong procedure to do that....
anyway the computer i'm using is a mac with osx 10.5 and i've installed the package
ifeffit 1.2.10 for intel.
thanks
           alessandro