Edit the included appsettings.json to update settings such as the update interval (CronExpression) and your Cloudflare token. You can also have it email you with failures and setup inclusion/exclusion lists, specify record type and some filters on which records to update.
Confused by those CronExpressions? I use: https://crontab.cronhub.io/
As for logging, I highly recommend that you change the logging path to an absolute location. Find the section "path": "Logs/log-.txt" and change it to something like "C:\some\path". Otherwise windows defaults the location to "C:\Windows\System32\Logs", which kind of sucks.
The application used Hangfire to schedule the updates, by default you can browse the scheduled via http://127.0.0.1:5080/ using the username "admin" with the password "password". You can change the port and credentials in the appsettings.json.
CMD: CloudflareDNSUpdate.exe install
CMD: CloudflareDNSUpdate.exe uninstall
