Installing

There are two types of add-ins that you can install.
Production Ready - These can be centrally deployed
Developer Add-ins - These are for testing

Developer Add-in - Using the Registry

HKCU\Software\Microsoft\Office \ 16.0 \ WEF \ Developer 

HKCU\Software\Microsoft\Office \ 16.0 \ WEF \ Developer \ "addin GUID" \ UseDirectDebugger 
HKCU\Software\Microsoft\Office \ 16.0 \ WEF \ Developer \ "addin GUID" \ UseLiveReload 
HKCU\Software\Microsoft\Office \ 16.0 \ WEF \ Developer \ "addin GUID" \ UseWebDebugger 

UseRuntimeLogging

HKCU\Software\Microsoft\Office \ 16.0 \ WEF \ Developer \ "addin GUID" \ RuntimeLogging 

add the (Default) value to your C:\Temp\LogFile.txt"