Mod does not seem to load or at least display any panel after update.

Strange.. try reinstalling it.
Working fine with my Server after the update...

Have reinstalled twice. No other ui mods installed except Skip Night which was installed before as well

Merged post

[Error] InfoPanel v0.9.8: Failed to load config file (is the config file corrupt?) (After parsing a value an unexpected character was encountered: ". Path 'Messages[1]', line 53, position 1.)

Merged post

Failed to initialize plugin 'InfoPanel v0.9.8' (ArgumentException: Could not cast or convert from System.String to Oxide.Plugins.InfoPanel+PanelConfig.)
at Newtonsoft.Json.Utilities.ConvertUtils.EnsureTypeAssignable (System.Object value, System.Type initialType, System.Type targetType) [0x00062] in <8fe7f8665ff548909c2f26d557e5093a>:0
at Newtonsoft.Json.Utilities.ConvertUtils.ConvertOrCast (System.Object initialValue, System.Globalization.CultureInfo culture, System.Type targetType) [0x00031] in <8fe7f8665ff548909c2f26d557e5093a>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.EnsureType (Newtonsoft.Json.JsonReader reader, System.Object value, System.Globalization.CultureInfo culture, Newtonsoft.Json.Serialization.JsonContract contract, System.Type targetType) [0x0008d] in <8fe7f8665ff548909c2f26d557e5093a>:0
02:00 [Info] Unloaded plugin InfoPanel v0.9.8 by Ghosst / Nogrod

That is an error with your edited config file, not the plugin itself.

Do we have to manually install the additions to the config or is it automatically added ? Do we delete existing config file before installing update ?

*Edit
I think i worked it out, I just copy/pasted the new additions into my existing config and they  show up ok, only puzzled as to where the "raw data" shown under config files on link gets entered ?
Good thing with this plugin is that you get an instant viewable result of what changes you make.