No such pseudo-hash field

This is the error you typically get when you incorrectly access an array as a hash, and have an old Perl that still does support pseudo hashes (such as 5.8.x).

In your specific case, your $license->{'properties'} is an arrayref, but you treat it as a hashref.

Something like this should work better

    my $maxEngine;
    my $props = $license->{'properties'};
    for my $p (@$props) {
        if ($p->{name} eq "maxEngines") {
            $maxEngine = $p->{value};
            last; 
        }
    }
[download]

Or, if you know for sure that "maxEngines" always is the first array field, you can say

    my $maxEngine = $license->{properties}[0]{value};
[download]

to retrieve the 42000.