I’m just going to give it a go to find out, but bear in mind there are currently known issues with uploading. The team is aware and working on it apparently.
I’m going to give it a go on Windows and share my process in case it’s helpful:
- I downloaded ant.exe. I right clicked in the folder ant.exe is in and selected ‘open in terminal’.
- I faffed around with ant -h to get a list of commands, then did ‘ant file -h’ and ‘ant wallet -h’ to get lists of commands for those.
- I figured I’d try adding a wallet with ANT in first, which will be needed for upload, so I did:
ant wallet import -p (password) (privatekey)
I also sent some Arbitrum ETH to the address so I could try uploading.
- Next, I wrote:
ant file upload -p (filename)
I entered my wallet password, then it paid for chunks and tried uploading, then worked 
Edit: First time I tried the upload failed, but now it’s been sorted! It was an error in payment contract, and now uploads are working, at least for smaller files (I tried 20mb and 26 mb with no trouble) 