Documentation is here: TA-TC-Sysmon-Transforms/README.md
Package TA-TC-Sysmon-Transforms subdirectory as tgz file, keeping the subdirectory in the package, and drop it into Splunk GUI, or bundle the addon via your deployment channels.
tar zcvf TA-TC-Sysmon-Transforms.tgz TA-TC-Sysmon-Transforms