After revoking my old token and generating a new one for certain reasons, I decided to add some custom paths for good measure. Here's what I added:

NSUI Saves /nsui_forwarders_data
Retroarch Saves /retroarch/cores/savefiles
Retroarch Savestates /retroarch/cores/savestates

Trying to run 3DSync after this resulted in a crash just after it finished warming up. Here's the dump:
crash_dump_00000002.zip

I guessed that maybe the spaces in the Name field might be causing the problem, so I replaced the spaces with dashes. It still crashed. Note that I first encountered this problem with the debug build you provided, but I also tried the current release and still got a crash. If needed, I could try to get some slow-motion footage of the screen before it crashes.

I'm using an Old 3DS.
While uploading some games like Smash Bros, Mario Kart and Mario 3D Land, the 3DSync app crashes. Unfortunately the crash message doesn't say much. I'm linking a video of the problem occurring.

Video

Hope this information enough, but ask me for anything if you need.

EDIT:

I was able to upload the Mario 3D Land file after I deleted all other save files.
My guess is that the upload endpoint hits the upload limit of 150mb when uploading a lot of files.

I wanted to use this software to sync saves between two 3DS consoles (JKSM).
I generated .ini file and it worked fine on first console.
On second console with the same .ini I'm getting:

Curl result: HTTP response code said error

The configuration page is currently broken, stopping new users from being able to configure 3DSync.

I'd love to see google drive and SFTP support added in a future release.
SFTP would be great for sending backups to my linux machine and google drive would be great for sending backups to my google and for syncing to my phone with Citra. (I don't use dropbox.)

Hello, I'm using the current .cia release on a N2DSXL running 11.12.0-45. It definitely uploaded some saves, but eventually it crashed. I tried again and the same thing happened. Here's the crash log from the most recent crash:
crash_dump_00000001.dmp.zip
By the way, I'm running Luma 10.0.1 and Fastboot3ds. Thanks!