To go along with the advice of Anonymous Monk...

Please list the specific modules that you are having trouble with, along with the output you get when you try to install them with cpanm. Also, I recommend that you do not install any other versions of perl until you have a better idea of what is causing your current issues (as multiple versions may alter your path in ways that can cause trouble). I currently use Strawberry Perl with App::cpanminus and I rarely have trouble installing modules. So, I suspect there is something wrong with your setup. If you give us more information, we may be able to help.

Update: The suggestion from Athanasius to install one of the PortableZIP editions is a good one. You should be able to download one of those, unzip the archive, and then run the portableshell.bat file contained in the root folder. Other perl installations should not interfere with it, and you can simply delete the entire folder if you want to remove it from your system.

Update #2: When installing a module with cpanm I often find it useful to use the verbose and prompt options to get more information. For example, to install Path::Tiny,

cpanm -v --prompt Path::Tiny
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