@crutledge - not sure what you mean? An LOI isn't a Sigil feature, so what you posted wasn't created by Sigil. Creating an inline TOC is certainly, but when I create one it most definitely has the paths to the files, and when I close and reopen the book they are still there. Inserting Links - has full file paths. Generate TOC for NCX - has full file paths.
Are you sure your book actually had full paths in the first place for that page? Attach an example with some repro steps if you think a problem exists.