Update - Windows 11 Works!: I ran the MS Win 11 checking program, and it flagged only the RAM as not meeting requirements, but it stated that as being 62 GB, not Kano's claimed 64 - probably being picky about measuring in decimal number system versus binary number system (really picky, Microsoft!!).
Turns out that was NOT a problem when I actually tried installing a preview version of Win 11 from a USB stick. It detected the C: drive as being about 57GB, with enough free space to install Windows 11, and to archive the base Windows 10 files for a possible roll-back (this was not including 1.1GB reserved in other partitions for recovery image and UEFI data). Looks as though it activated Windows 11 with the built-in license for Windows 10 as installed by Kano at the factory, so hoping it will stay activated after the official release in October without a re-installation. Windows updates have been applied several times, so it may be simply updated some more when the "gold" version is released in October for general use.
At any rate, it seems you cannot believe the checking program if it ONLY disqualifies a PC due to the total disk space, and your computer has close to 64 GB disk storage (whichever number system is used...). If you have Windows 10 on the PC now, and want it to be saved for a possible roll-back after installing Win 11, then deciding you don't like it, I guess you should have at least 25-30 GB free for the Win 11 installation, plus the Win 10 archive, and whatever else is using space such as your user files/programs. Move whatever you can to a flash card, at least until after the installation, and use the file manager to run full disk compression, if you have not already done so. Then see what can be restored to the C: drive after the Win 11 installation.