Like I said, XWE is not nearly as stable an environment as SLumpEd. You need to constantly back up any files you're editing on XWE, especially when you're modifying text lumps, or you could find your file corrupted by a slight change. However, XWE also has way more features and a better interface. Just trying what you did in SLumpEd in XWE may fix your problem...assuming XWE doesn't corrupt your file.