Before I tried your solution on Windows 10 with Active Perl,

tryit.pl a b c

using the ".pl" association to invoke Perl did not work, but

perl tryit.pl a b c

did work.

Then I tried your solution of adding %* to reg entries with "C:\Perl64\bin\perl.exe" "%1", and that fixed it so now

tryit.pl a b c

works and can see ARGV. Thank you!