the array is populated in the following manner

   eval(" push \@reg_map${page_counter},\[\"\$var01\",\$var00,\"$var02
+\"\]");
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Eek. So you have something like @reg_map00,@reg_map01,@reg_map02,..?

Whenever you are tempted to add a counting suffix to any variable, use an array instead:

• Instead of @reg_map00,@reg_map01,@reg_map02 use @reg_map - $reg_map[0], $reg_map[1], $reg_map[2]. If you want to store arrays in those slots, use anonymous arrays.
• Instead of $var01,$var00,$var02 use @var - $var[1], $var[0], $var[2]

No need for eval then:

push @{$reg[$page_counter]}, @var;
[download]

Think of eval as a costly subshell under the control of you program in its own sandbox¹. Setting that up only to push to an array is overkill, convoluted, difficult to read and maintain.

Whenever you are tempted to use variables using a stem and a suffix, e.g. $some_foo, $some_bar, $some_baz - use a hash instead:

%some = (
    foo => ...,
    bar => ...,
    baz => ...,
    ...
);
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This makes your code cleaner, more readable, more maintainable, and it makes constructs like your eval push unnecessary.

¹) Not quite a sandbox proper, since even string eval gets the surrounding lexicals, let alone (package) globals.