Feature caching and partial runs are a great addition to FME 2018 but are limited to the main workspace canvas. It is currently (FME 2019.0) not possible to initiate a partial run from within an embedded custom transformer. It would be great if this could be enabled.
This enhancement would complement the similar request listed in this Idea:
https://knowledge.safe.com/idea/76399/feature-caching-and-custom-transformers.html
(It would also be great if "partial run" and "feature caching" topics could be created for tagging KB Ideas/Questions as these do not currently exist and the closest I could find was the old terminology of "run with full inspection".)