Thanks. The install eventually worked after multiple attempts so won't use this right now but I was interested to learn about the CPAN configuration options. I found a description of recommends_policy at Config Variables. I found the location of CPAN/config.pm that CPAN is using along with the current value of recommends_policy from the CPAN shell like shown below. This also gave me the command o conf help.

cpan> o conf
$CPAN::Config options from C:\Strawberry\perl\lib/CPAN/Config.pm:
    commit             [Commit changes to disk]
    defaults           [Reload defaults from disk]
    help               [Short help about 'o conf' usage]
    init               [Interactive setting of all options]

    applypatch         []
    auto_commit        [1]
    build_cache        [50]
    build_dir          [C:\STRAWB~1\cpan\build]
    build_dir_reuse    [0]
[...]
    recommends_policy  [1]
    scan_cache         [atstart]
    shell              [C:\Windows\system32\cmd.exe]
[...]
[download]