Can't restore Acekard 2i's flash to R4i Ultra

[pxdl]

Everytime I try to restore an ak2i flash to my R4i Ultra (r4ultra.com) (direct ak2i clone made by team acekard with the same hardware) it gets stuck at the same spot, as shown below:

I am able to restore an ak2i flash to the r4i ultra using Decrypt9 just fine, but not with ntbroot_flasher.

[ghost]

Could you try the latest release? Getting stuck at 49% was a general AK2i problem in some more recent post-0.1.2 but pre-0.2 commits.

[pxdl]

Tried the new 0.2 version, still gets stuck at the same spot.

[pxdl]

I tried it again, but now with ntrboot_flasher 3.1 and with loglevel switched to debug.
The top screen got stuck at "writing chunk 001F0000" while the bottom screen had a progress bar which was moving slowly until it got stuck at 50% and I had to do a force shutdown.
Here's the log file:
ntrboot.log

[pxdl]

Some PCB pictures:

[MushGuyDS]

Same problem here, but instead it kept getting stuck at 25% with latest release.