whew...Okay, mass reply here:
Maxxed:
1. Hold the stylus down on some blank space on the main page and go to Page>Wallpaper, select the black background from that theme's folder.
2. Yes, the wifi detection will still work.
Jhuroleye:
1. see above
2. I had this problem once too, here is the fix:
Go to File Explorer and travel to Windows\StartUp, IMDefault should be in there, if it is not (it probably isnt, since it isnt working), you need to go to Windows\Programs\ and tap and hold on IMDefault, select Copy. Go back to that startup folder and tap hold some empty space and select paste shortcut.
Suprmatt:
1. To actually add the variables, I do not think it is possible. You can select different accounts by setting the text to %Unread:XXXX%, with the XXXX being your account name (exception: ActiveSync instead of Outlook E-Mail)
2. I'm not sure whats up with the calendar thing you speak of. is the date set correctly in Windows Mobile? and what's the text display set to in WAD?