I contacted the author of the package, but the email address is no longer valid. Then I contacted Stata, and they replied as follows:
"The author would need to make the change(s) and repost the command. We don't have that ability. From a simple search, it appears this has come up in the past. From previous responses, you can manually remove the letter B at the end of iskoisei.ado (as you've done). After that it will work."
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