It's not just Macrium Reflect, all imaging/cloning utilities can run into the same problem with Windows 10. Which other utilities did you try with Win10 that worked better than Macrium Reflect?

Fast Startup is a sort of hibernation system, and by default most imaging/cloning utilities do not preserve the pagefile or hiberfile.

I'm not sure about the exact mechanics of how Fast Startup works, but I presume it's effectuated via the BCD and hiberfile. Thus, if you make an image that excludes the hiberfile it shouldn't be surprising that the system may crash when you try to boot that restored image.

When you boot a system that had been shut down with Fast Startup, it pulls stuff out of the hiberfile (and pagefile?) to repopulate RAM instead of rebuilding the RAM contents from scratch. That can save a bit of time, but most users are unaware how distinctly different this is from what you've come to expect from cold booting in the past. In essence, Windows isn't being fully shut down. In the past, you knew what to expect when you cold booted a computer, but Fast Startup skews that because it's not truly a cold boot anymore.

Incidentally, that's why you should be skeptical of boot time comparisons between Win10 and earlier versions. Often they compare the hibernated Fast Startup to a true cold boot of the earlier OS. It may seem like Win10 boots way faster, but if you compare a true cold boot of Win10 to Win7 it's only slightly faster (if at all--I don't boot my Win10 that often, so when I do it's always doing some update or other that slows the boot process way down).

By disabling Fast Startup you force Win10 to completely shut down and start with a true cold boot the next time the computer is turned on.

BTW, I believe Fast Startup comes into play only when you "Shut down" the computer. My understanding is it does not come into play if you choose "Restart" instead of "Shut down". Thus, I think you can expect different results if you "Restart" to boot your imaging boot media vs. "Shut down" and powering back on. I haven't confirmed that because I leave Fast Startup disabled on my system, but that would be my assumption.