I have 50 achievements to upload to iTunes Connect. I have read that you can do this using iTMSTransporter however I cannot find references or examples of the script or meta
You can download metadata specifications and the iTMSTransporter manual
from iTunes Connect: https://itunesconnect.apple.com:
iTMSTransporter manualYou can also get help by executing iTMSTransporter -help [command].
While I'm not familiar with uploading achievements I've written a Ruby gem that contains a small command line program that might help you:
https://github.com/sshaw/itunes_store_transporter#readme
I also have a GUI (still somewhat rough around the edges) that might help: https://github.com/sshaw/itunes_store_transporter_web/sshaw/itunes_store_transporter_web#readme
Apple has created iTunes Connect Resources & Help.
Film & TV specs are there too.