X12 Studio writes logs according to the application configuration XML file contained in the X12 Studio installation directory, by default:
C:\Program Files (x86)\Tallan\T-Connect\X12Studio\X12Studio.exe.config
Logging is done using the Serilog Logging framework. Logs setup by default to write to the following two locations:
Files in following default folder, which can be changed int eh X12Studio.exe.config (above).
Additionally, logs are written to the Windows Application Event Log