If I understand your question correctly, youare tryg to send data from the main program(file) to the module. I recently did that, and here is the code I used (names modified to protect the innocent):
MAIN code

my $ProgramDir;
BEGIN{
   ($ProgramDir) = ( $0=~m|(.+)\/.+$|, $0=~m|(.+)\\.+$| ,".");
}
use lib ( $ProgramDir, ); # Current Program's Dir
use MyModule ("$ProgramDir/MyModule.db3");
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Inside the Module:

!/usr/bin/perl -w
use strict;
use warnings;
use Class::DBI;

package MyModule;
our $DBPath="MyModule.db3"; # Default file nme
sub import{
   my ($class,$newpath)=@_;
   $DBPath = $newpath || $DBPath;
   ## print "IMPORT: Setting path to '$DBPath'  \n\t \n";
   ## Delay this setting till AFTER IMPORT !!
   MyModule::DBI->connection(qq|dbi:SQLite:dbname=$DBPath|, "", "");
}
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"import" gets called automaticall, on "use".