I used the below scripts to test with both 4.66 and 4.67. The Call command seems to call the the second script fine with both. I was not able to reproduce the error you are getting. Are you certain the error is not being generated by the Called script, as the call will get an error returned from the second script.
Loc: New Jersey
Regarding the original question - While Kix is forgiving and may work when things aren't quite right, the name of the file being called is an argument to the Call command. The argument is a text string, and as such, should be enclosed in quotes. The problem would be exacerbated if the string began with a number. (OK - not likely [possible!!] with a UNC path, but think about assigning a simple file named "40Lines.udf" to the call command.. what do you think Call would search for?
I've never not quoted this argument and treat it just like variable assignment, which should place strings in quotes.
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