Could not start compilationException: Failed running ScriptUpdater.exe its output is:stdout:
[Script Updater] Assets/Scripts/Engine/BuildCharacters.cs (73, 16) Could not find the best candidate for 'Characters.Where(?)' expression (Error: ArgumentTypeMismatch, AmbiguousMatch). This may cause expected updates to not be applied.
[Script Updater] Assets/Scripts/Engine/BuildScenes.cs (113, 16) Could not find the best candidate for 'Scenes.Where(?)' expression (Error: ArgumentTypeMismatch, AmbiguousMatch). This may cause expected updates to not be applied.
The kind of code it fails to update is similar to

return Characters.Where(x => x.Episode == episode).ToArray();

where Characters is defined as:

public static Character[] Characters{ get { return _characters; } }
private static Character[] _characters =
{
new Character("Hulk", Combatant.eCombatantType.Hulk, Episode.Hulk),
new Character("Abomination", Combatant.eCombatantType.Abomination, Episode.Hulk)}

Attached Editor.log file might have more info. If you need the project (very big), you can get it from \\HOMES\qa\BigProjectsImporting\AvengersAssemble_4.3.zip