A 'friend' moved to Aus about 10 years ago with a UK CAA Frozen ATPL. CASA do not recognise frozen ATPLs and, therefore, only recognised the CPL part. His requirements per CASA were:
CPL Air Law Exam
IREX Exam
All 7 CASA ATPL Theory exams
Combined ATPL/CPL skills test - completed on a ZFT TR course with a major airline.
The airline then managed the package of tests and exam results and sent them all off to CASA - by return was a CASA ATPL and Type Rating. Took them about a year altogether, but they were sponsored by the employer.