Your extension is executed by the adTempus Job Host process adTempus.jobhost.exe (or adTempus.jobhost32.exe for extensions that require 32-bit execution on 64-bit computers).
If you need to pass settings to your extension using an app.config file, you can edit the adTempus.jobjost.exe.config (or adTempus.jobjost32.exe.config) files to make those settings.
The Job Host process creates a log file using log4net. If your extension uses log4net, log messages from your extension will be included in the log file produced by the Job Host. By default the Job Host uses a BufferingForwardingAppender and only writes to the log file if a Warning or Error message is logged. You can switch this to log all messages by editing the configuration or using the adtloggingconfig.exe program to change the setting.
Log files are written to the TEMP folder of the user whose account the job is running under. Each instance of the Job Host has a separate log file, named adtempus.jobhost.nnnn.log, where nnnn is the Windows process ID (PID) of the host process.
Old log files are periodically purged by the host process.