Excellent

The problems were twofold:
1) Older versions of Audacity do not handle extended character sets very well (improved in recent versions of Audacity)
2) WordPad (and Microsoft NotePad) implement Unicode "the Microsoft way" (aka "incorrectly"), and automatically change the character encoding of the document.
Two things I would suggest:
1) If you've not already done so, upgrade to Audacity 2.2.2 at your earliest convenience.
2) Don't use WordPad (or NotePad) to edit AUP files. Generally, you should not manually edit .AUP files at all, but if you have to, use NotePad++, which by default uses the character encoding of the original document.