Hi Tom,
For the Aircreation, these are the settings used for my Window.xxx settings (Window.00 - Window.04) in the panel.cfg file that work for me.
Code:
[Window00]
file_1024=AirCreation_582SL_background.bmp
//position=7
size_mm=1024,768
window_size=0.333, 1.000
window_pos=0.333, 0.000
visible=1
ident=MAIN_PANEL
gauge00=Aircreation_582SL!altimeter, 326,624
gauge01=Aircreation_582SL!compass, 456,624
gauge02=Aircreation_582SL!asi, 585,624
gauge04=SimIcons1024!Other Controls Icon, 446, 744
gauge05=SimIcons1024!Kneeboard Icon, 468, 744
gauge06=SimIcons1024!ATC Icon, 490, 744
gauge07=SimIcons1024!Map Icon, 512, 744
gauge08=SimIcons1024!GPS Icon, 534, 744
gauge09=SimIcons1024!Radio Icon, 556, 744
[Window01]
BACKGROUND_COLOR=0,0,0
size_mm=208,129
//position=8
visible=0
ident=RADIO_STACK_PANEL
window_size=0.080, 0.320
window_pos=0.920, 0.680
gauge00=Handheld_Radio!radio,0,0
[Window02]
size_mm=545,354
//position=2
BACKGROUND_COLOR=0,0,0
VISIBLE=0
ident=GPS_PANEL
window_size=0.155,0.3625
window_pos=0.690, 0.620
gauge00=fs9gps!gps_295, 0,0
[Window03]
file=AirCreation_582SL_popup_background.bmp
windowsize_ratio=1.000
//position=6
size_mm=146,226
ident=MISC_POPUP_1
window_size=0.080, 0.320
window_pos=0.590, 0.680
gauge00=Aircreation_582SL!fuel, 16, 142
gauge01=Aircreation_582SL!rpm, 18, 17
gauge02=Aircreation_582SL!ignition_switch, 97, 140
[Window04]
//position=7
size_mm=1024,768
child_3d=1
background_color=0,0,0
ident=MINIPANEL
window_size=0.100, 0.400
gauge00=Aircreation_582SL!altimeter, 326,624
gauge01=Aircreation_582SL!compass, 456,624
gauge02=Aircreation_582SL!asi, 585,624
You can either try copying and pasting the above code into your panel.cfg file for the aircreation (pasting over the Window.00 - Window.04 entries), or you can use the code for comparison against your edits to try to determine where you need to make changes.
In any case, as John said, you don't have to set the window_size to 0.333, 1.000. You can start with window_size=0.250, 0.500 with a window_pos of 0.5, 0.5, and then you can tweak the window's size and position from there.
Hope this helps. :)
-George
Edited to add: For many of the default aircraft, the GPS window has a size defined as "window_size=0.5". Remember to either make your size changes to that line, or to comment it out and add a new line with the values you wish to use. This is because adding a second "window_size=" value will be ignored for that window, so either the existing one needs to be edited or commented out to get your changes to show. I just wanted to point that out, as that's messed me up a couple of times. :P
Edited again, to add: Since my involvment in this thread, I've also gone and started editing all my aircraft panel files (and backing up the modified ones as I do so) for position and size, instead of my previous 'quick and dirty, 0.333 and call it a day' methods (thanks for giving me the incentive to do this, John.) As such, I've got a few done (and doing more each day), so if you're stuck on an aircraft, post here, and possibly either John or myself has already done something with that aircraft, and can help get you through it by sharing our code and/or .cfg files if needed.