Have some bad news for you. This line here:

$ReturnVal = $process.GetOwner($strUser, $strDomain)

is not supported in Kixtart. It takes two parameters that are defined as OUT and Kixtart wont dynamically create them for you. You would need to find another way to get this information (say, as properties) but a quick scan of MSDN yields nothing for this (did only a quick search).