To install just CA Compress for IMS only the following FMIDs are required:
CITKG00 /* IMS Toolkit Common Component */
CASTG00 /* CA Compress Data Compression for IMS */
If the UNLOAD job for example
UNLOAD EXEC PGM=DFSRRC00,PARM='ULU,DFSURGU0,&DBD,,,,,,,,,,,&DBRC',
STEPLIB DD DSN=CAIMS.SHRINK.IMSUT.LOAD,DISP=SHR
DD DSN=IMS.IMSYSSxy.SDSFRESL,DISP=SHR
DD DSN=IMS.PRD.EXIT.RESLIB,DISP=SHR
DD DSN=IMS.PRD.RESLIB,DISP=SHR
then executed it fails with U4004 on step UNLOAD:
+IDI2302E MODULE "IDIDBOM " COULD NOT BE FOUND IN THE LIBRARY 00040000).
+IDI5603E UNABLE TO LOAD SUFFIXED LOAD-MODULE: IDIDBOM . RC=08
IEF450I IMSICUOF UNLOAD UNLOAD - ABEND=S000 U4004 REASON=00000000 371