I guess I didn't test thoroughly enough! Apologies for the busted release; a fix is being published to the gallery shortly!
Here are the fixed files, and they'll be up on the gallery in a few minutes. 😄
For those of you wanting to continue your koans run uninterrupted and without resetting, please run the following command to replace your file headers for compatibility:
Get-ChildItem -Path $env:PSKoans_Folder -Recurse -File | ForEach-Object {
( Get-Content -Path $_.FullName ) -replace '^#Requires.*PSKoans','using module PSKoans' |
Set-Content $_.FullName
}