So... update. I tried the 32 bit image, and put it in Virtualbox. It didn't get to much; I assumed because there wasn't enough power to boot it.
So I tried the USB, and behold, it worked. After disabling the UEFI secure boot in the BIOS at least.
But, it didn't exactly "work" all the way. After a lo-o-ong time I got to the language selection -the it crashed and started over. Then I got to the license, and it crashed again. Then again. Then I got to the wifi selection. Then it crashed.
I conjectured that the connection to the usb, having to reach through the pins on the hinge, was being inefficient. So I tried booting via OTG, using a double-ended pen drive sporting a microUSB too.
Good news: it works. You have to select USB boot before Windows in the BIOS, and then wait 20 seconds since the grub is not touch enabled, but it boots. So you could easily use RemixOS in tablet mode. If you don't mind the USB sticking out.
The bad? It works exactly like the first option. That is, not enough to be useful.
Also, at the end the USB was scalding hot, which can't be good.
So, is my USB faulty, or my image, or both? Or is RemixOS just incompatible with my hardware in general?
The only path I see now is to make enough room, and then summon enough courage, to install on the hard drive.
I'll probably get to it, but only after my main workstation is back from the dead.
Any other advice?