I had to make the following changes:

• Add a $ to the typeglob line: *{$caller . '::' . $name} = \%magical_hash;
• Do a two-step reference creation in TIEHASH():

  my $self = 'fake';
  $self = \$self;
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• Use a more standard use statement: use Eval (':');

It won't run under strict, though, with the symbolic reference in the import() bit.