I am down the bottom end of the Darling River near Wentworth, New South Wales.
Yes the 600 high for Erio-WA screen, to cater for the netbooks and such market to provide wider compatibility for distribution.
The number 2 problem is most probably with the sticky window, and you not giving focus back to Erio-WA again. This only happens when Cancel out of the font selection window, I get no serif/sans selection window, and I would think that would be the normal operation as I am cancelling the operation. If I click on Ok I get the serif/sans selection window, so after it is closed Erio-WA gets focus again.
I hope you can follow this explanation, cant think of a better way.
I thought of a way you might want to implement for the smaller screen height, without having to change your layout.
OpenWindow(0,0,0,800,700,"Set Window Size For Screen Size",#PB_Window_SystemMenu|#PB_Window_SizeGadget|#PB_Window_ScreenCentered|#PB_Window_Invisible)