I see a few problems

urls are hardcoded ...

debugging via log ... eew

$global_session ... super yuck

random suspicious or die on $! usage not seen in the docs

CGI::Application::Plugin::Session is broken as session_config seems to have no effect

your logic is fudgy, you don't use P/R/G

both collect_data and display_data are the same form, and pretty much the same code, and in both codes you fetch data from the $cgi_query and not from the $session -- this is fudge -- and in both display and collect you save data into session -- display is display

I think having templates and logging and "everything" is confusing you (it confused me), its just a lot of stuff to juggle

You should start with pictures, for example 

collectPage
    presents a form
    processes form submission
       if got valid data
           save data into session
           redirect via get to displayPage
       if got invalid data
           show form again
           while explaining what data is bad

displayPage
     if session 
          display data from session
     if no session
          give link to collectPage

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In reply to Re: Checkbox parameter not being stored in CGI::Session by Anonymous Monk
in thread Checkbox parameter not being stored in CGI::Session by perlron

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