It is not like you have *any* other options, and as a matter of fact having it on a slow setup is not at all bad when experimenting.
But I see that you are looking for a pre-made solution:
the problem is not Win7PE vs. Win10PE (they are similar enough, at least for a basic PE) the issue is the vs. Win10ARMPE.
The whole ARM stuff is very recent, noone (set apart from you) has such a machine (yet), and noone (again yet) even knows the booting mechanism, the files involved, etc., the documentation is scarce, etc.
Given the MS attitude for code re-use, it is very likely that there are enough similarities, but I believe that there are enough differences (due to the different architecture) that some serious experimenting is needed.
It is true what you say about a slow system being advantageous for testing sometimes, but I have already "bit the bullet" and powered on the ARM64 device, which is currently running in S mode, so there is little reason left for such an expensive approach time-wise.
You cannot transition back to S mode after upgrading to full Windows 10 Pro, which may be something I may have to lose ultimately, because you cannot do anything in S mode (you would probably not even approach S mode from orbit if it were on another planet). However, I suppose, a good starting point might be the Windows RE that is included with the ARM64 laptop!!!
In fact, if we can find a way to add the 32-bit WoW (Windows on Windows) subsystem to this ARM64 Windows RE image, that would suit all of my requirements perfectly. I can run any imaging tool I like easily. In fact, I would like to try this quickly, maybe even without messing with the S mode situation. Do you know how to add WoW support to an existing Windows RE/PE image? Again, I would need to be able to do the process by running a few scripts here and there (most probably after booting into RE mode, from the command line there).
Maybe I can even run EXE in RE mode on the device, since that would sidestep all kinds of S issues...
BTW Macrium have also confirmed they don't support ARM64 at the moment, so the best is to really add WoW to RE.
Edited by armixen, 4 weeks ago.