I don't tell that my way is the most right and reliable, but it works and covers all my requirements.
I have installed three portable versions:
C:\somewhere\on\my\pc\strawberry-perl-5.8.8.3
C:\somewhere\on\my\pc\strawberry-perl-5.16.2.1-32bit
C:\somewhere\on\my\pc\strawberry-perl-5.30.0.1-32bit
I have the soft link
C:\somewhere\on\my\pc\Perl pointing on one of these directories. It is created with
mklink /d or
mklink /j and declared in
%PATH% variable. So every time I have full access to one of the Perl instances. If I need to switch to another instance (version), I remove the previous link and create another one pointing to another instance.