I don’t know if it works properly on anything else than MS Office (excel), you can give it a try of course but I have never tested it on anything else but Excel.
You should be able to punch the CRJ 700 in there if you have all the data. For bigger planes it might be a bit harder to find the performance and mass & balance data as those numbers might be published in separate performance and weight and balance manuals rather than in a POH or AFM.