--- file \this\path\gui\skills_gui.pm --
package skills_gui;
...
----------------------------------------
--- file \this\path\db\skills_db.pm --
package skills_db;
...
---------------------------------------=

--- file \that\path\gui\skills_gui.pm --
package skills_gui;
...
----------------------------------------
--- file \that\path\db\skills_db.pm --
package skills_db;
...
---------------------------------------=

##</code><code>##

---- File: \some\other\path\yourscript.pl ---
use lib $ENV{LIB_PATH};
use gui::skills_gui;
use db::skills_db;

....