So I’ve been poking around trying to create an omnigraffle document in a text editor (TextWrangler). I started out creating and saving a document in omnigraffle containing a single circle. Unfortunately, when I edit the file in TextWrangler I cannot open it in omnigraffle anymore! I tried removing and adding back a single character, so that there would basically be no change at all; still I’m presented with the error message “The document “name_of_the_file” could not be opened.”.
I think the error is caused because omnigraffle checks the modification date of the file, creates a hash-value of it and compares it to the string value under “NSPaperName” (which to me appears to be a hash value of some sort).
Does anybody know how this hash value is generated or if there’s something that I’m missing? I would really like to use omnigraffle for this, but as of now I have been forced to continue the work using MS Visio XML file format and importing it to omnigraffle.