The Java Transformers started task requires a complete OMVS segment including an UID, HOME and PGM attributes. The requirements are the same as the CA Spool started task. The documentation reference is:
Regarding security of the Java Transformer task, the permissions of the documentation are for CA Spool but they are the same for the Java Transformer started task. As long as the userid has a complete OMVS segment you can use the same userid for CADRAS and the ESFD2EB started tasks.
Apply all published maintenance for the Java Transformers
These are the directories that are updated during the Transformers usage, that is, files are created and deleted from those folders during report transformation. So, you may want to keep them separated from the original directories created by the Transformers installation.
In particular, the /apps directory is the place where you may have your customized transformation parameter files. if you use the /apps installation directory you may lose your customizations when you apply maintenance (PTFs)
The /input and /output folders are the ones that may require additional space as depending on the size of the reports being transformed you may need more space in the zFS dataset than originally allocated during the installation. Again, keeping the directories in a separate, bigger zFS dataset may be a good idea.