question on using multiple forms in an application

Hi,

I create an application using multiple forms and each form is opened by calling open_form(form1_name, activate, session). When I navigate between each independent form, sometimes my stacked canvas in one of the form is shifted to the left of my screen instead of staying at the center. Also, my window is resized when I navigate among the forms. I have maximized all them in When-new-forms-instance and When-Window-activate and When-form-navigate triggers.

Have anybody experience this kind of behaviour before in Forms 4.5? I am using Oracle Developer/2000 1.5 for NT.  

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