With regards to ratings issued by another ICAO member state.
When i joined, it was a condition for me to get the rating endorsed on my JAR/EASA license, prior to joining.
Unfortunately there is no good reason for this, as they make you sit all the exams again...
It was a bit of an issue for me. First of all getting the time off to do it, when living in the ME, and then not to mention the cost involved in having to resit the exams in the UK, as well as paying for 4 hours in the sim with an examiner...
BTW seems like they have just opened up for A320 rated pilots again.