Spamiky, a Preview of your CorelXARA file fails when opened in a browser so you will have to load up each old file, copy into a blank file and save that.
You could trying Expandxar.exe; this is a zipped command line utility that might unpack your CorelXARA 1.1/1.2 files for use in Xara v15. Again, each file needs to be saved as a new one.
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