Save game loads but then cannot re-save.

[Sunblood]

Steam version.
Save file: https://dl.dropboxusercontent.com/u/1499536/Welsh.rws

Mod list: http://imgur.com/a/wYfJ7

Error message: http://pastebin.com/zJPjrKwT

I can load the save and continue play without issues, but when trying to re-save (manually or autosave) I get the error message. No new save is created.