Creating Userdata seems to be buggy with Windows, I would try to concentrate on that since the flash process itself was working...
Note, “make_f2fs failed: 3221225477
fastboot: error: Cannot generate image for userdata“
This error usually means your Android sdk is not meant for the version you're about to install (to old) so ensure the binary which you are using is the one delivered with the rom.zip.
Also, some people advice to keep the folder name as short as possible.
With this guide of ours, you'll be able to learn all the fastboot commands and their syntax. We've also posted some hidden commands which you never knew.
android.tutorials.how
Fastboot is capable of formatting / erasing particular partitions, so formatting userdata can be done by yourself, just decompile the script and see if you can do the make2fs part manually, this should render the phone working again, flash eu rom once more, maybe on native Linux?
Regards.
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