Problem solved! The codepage for PuTTY sessions with the problem were set to UTF8. The session for the server that didn't have the problem was set to "ISO-8859-1:1998 (Latin-1, West Europe)". I chaneg the setting from UTF8 and YaST is now displaying properly.
...and I thank you for reporting back, this will for sure help others that run into the same situation!
From the times when today's "old school" was "new school"
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