Reproduction steps:

1. Change your time zone to UTC +8 (Philippines)
2. Open "unity-timezoneinfo-bug.zip" project
3. Open the "Main" Scene
4. Enter Play mode

Expected Result: No errors should appear
Actual Result: NullReferenceExpection is thrown

Reproduced with: 2017.3.0a2, 2017.2.0b5, 2017.1.0p2, 5.6.3f1, 5.5.4p2

Note:

Error on Windows 10:
TimeZoneNotFoundException: Exception of type 'System.TimeZoneNotFoundException' was thrown.
System.TimeZoneInfo.get_Local ()
MainScript.Start () (at Assets/MainScript.cs:7)

Error on Mac (10.12.2):
NullReferenceException: Object reference not set to an instance of an object
Is only thrown on some TimeZones //System.TimeZoneInfo.GetApplicableRule(DateTime dateTime)
System.TimeZoneInfo.IsInvalidTime(DateTime dateTime)
System.TimeZoneInfo.IsDaylightSavingTime(DateTime dateTime)
System.TimeZoneInfo.GetUtcOffset(DateTime dateTime)
MainScript.Start () (at Assets/MainScript.cs:7)

You can fix this error by setting the Time zone to, for e.g., UTC +2 (Vilnius) (Works only for Mac)

For Mac, where you put the pin for the TimeZone can determine if the error is thrown or not, very random though

Happens in Countries:
Philippines
Brazil
Moscow
etc.

Doesn't Happen in:
Lithuania
Greenland
USA
etc.

Update: Using the 4.6 mono runtime and classlibs fixes this issue.