StarTools keeps a detailed log of what modules and parameters you used. This log file is located in the same folder as the StarTools executable and is named StarTools.log.
As of the 1.4 beta versions, this log also includes the mask you used, encoded in base64 format. See the documentation on masks on how to easily decode the base64 if needed.
Final signal compositing is delayed until it is convenient and mathematically optimal.
The Heal module was created to provide a means of substituting unwanted pixels in an neutral way.
You are forgiven if, at first glance, you get the impression StarTools offers only the basics.
You can convert everything you see to a format you find convenient. Give it a try!