G'day fsmendoza,

I've always found that Tk::grid, rather than Tk::pack, is the better geometry manager for this task.

I would, however, advise that you lay out your GUI with frames (Tk::Frame, or even Tk::LabFrame) using pack. Then, within whichever frame(s) you want for your label and entry widgets, use grid.

You should also aim to avoid a monolithic script with all variables having file-scope: not doing so leads to all the same problems experienced with global variables. You're already using lexical variables, which is good; limit their scope within subroutines, anonymous blocks, or similar constructs.