1) The icons do not show up on the lock screen

Old, 3rd party icons are not updated to work with iOS7. You have two choices:

A) Install SameStatus. This will shrink your lock screen statusbar and make it the same as the home screen statusbar

or

B) You can manually create iOS 7 lock screen versions of the icons. The icons are located in /System/Library/ Frameworks/UIKit.framework/. You need to find all of the icons in that folder that do not work on the lock screen. Each one should have files named Black_ON_Name.png and Black_ON_Name@2x.png. You need to make duplicates of those 2 files for every icon that does not work and rename the duplicates to LockScreen_ON_Name.png and LockScreen_ON_Name@2x.png.

Personally, I would go with the SameStatus option. I hate the fact that the lock screen statusbar is larger than the home screen one and can't imagine what designer at Apple though that was a good idea.

2) The icons do not show up while App store apps are open in the foreground

OpenNotifier does not show any statusbar icons while app store apps are open.

OpenNotifier shows statusbar icons while in Messages, Notes, Phone, Maps, Settings but not in Mail or Safari.

OpenNotifier shows statusbar icons while in Cydia, iFile, Flex, Firewall iP but not in iCleanerPro.

These issues are because of limitations with the underlying library (libstatusbar) that is used by OpenNotifier.

Update to the newest version of libstatusbar (0.9.7.1.2 or newer)

3) Icons do not work for the stock Mail app

Badges must be turned on in Settings -> Notification Center -> Mail.

If you do not want a badge on your mail icon, use Settings -> OpenNotifier -> Hide Mail Icon Badge.

4) How do I create my own icons?
You must respring after adding icons in order for them to show up in the statusbar!!!

in /System/Library/ Frameworks/UIKit.framework/ each icon needs 6-9 png files for iOS 7+ to create black and white statusbar icons.

Height = 20 pixels
Black_ON_Name.png
Silver_ON_Name.png

Height = 40 pixels
Black_ON_Name@2x.png
Silver_ON_Name@2x.png

Height = 60 pixels (this is to offer better support for iPhone Plus models, although you can get away without it them)
Black_ON_Name@3x.png
Silver_ON_Name@3x.png

The lock screen icons are larger, but you can use the same sizes as above, that's what I did.

Height = 24 pixels
LockScreen_ON_Name.png

Height = 48 pixels
LockScreen_ON_Name@2x.png

Height = 72 pixels (iPhone Plus models)
LockScreen_ON_Name@3x.png




Height = 20 pixels
Black_ON_Name_Color.png
White_ON_Name_Color.png

Height = 40 pixels
Black_ON_Name_Color@2x.png
White_ON_Name_Color@2x.png

Height = 60 pixels (this is to offer better support for iPhone Plus models, although you can get away without it them)
Black_ON_Name_Color@3x.png
White_ON_Name_Color@3x.png

Height = 24 pixels
LockScreen_ON_Name_Color.png

Height = 48 pixels
LockScreen_ON_Name_Color@2x.png

Height = 72 pixels (iPhone Plus models)
LockScreen_ON_Name_Color@3x.png




Follow the conventions above, but add "Count_%d" before "Name" for all versions except for Silver. For Silver add "Count_" before "Name"

Black_ON_Count1_Name@2x.png
Black_ON_Count2_Name@2x.png
[...]
Black_ON_Count10_Name@2x.png
LockScreen_ON_Count1_Name@2x.png
LockScreen_ON_Count2_Name@2x.png
[...]
LockScreen_ON_Count10_Name@2x.png
[...]
Silver_ON_Count_Name@2x.png

5) OpenNotifier does not work or your device is booting into SafeMode because of it.

rename the file /var/mobile/Library/Preferences/ com.n00neimp0rtant.opennotifier.plist

to

com.n00neimp0rtant.opennotifier.plist.bak

rename the file /var/mobile/Library/Preferences/ net.tateu.opennotifier.plist

to

net.tateu.opennotifier.plist.bak

and respring. This will wipe out all of your current OpenNotifier settings and allow you to start fresh.