TTone backup and upgrading to a larger SD card

Hi,

I have a lot of dumb questions, I hope they are not too dumb to get an answer :)))

I have a TT One (I guess its a v4, it says 4N00.012 on the bottom) and DeviceVersionHW=ONE (v4) on /ttgo.bif

It still have the original 256 Mb SD card and the last map update was about 5 or 6 years ago.

I'm starting to read all the stuff here in order to do the upgrade but 1st I'd like to know if it's possible to do a true backup.

I've red about copy all the files with windows explorer but I don't trust it much.Is doing an image with Win32 Disk Imager saffer than just copying all the files ? I do fear to lose some hidden or system marked files, I never know what's win 10 doing. So a low(er) level copy looks to be safer. Is this correct ?

On the other hand, is the SD card all the storage on this device ? There's no boot flash inside ? I noticed that there is a flash erasing tool on the TT site but I'm not sure if it applies to this model ? And if it does, does it have code there or it's only a non-volatile memory area for some configuration?

In other words, if I just remove the 256 Md card and got a brand new 2 Gb SD (4 Gb would require a newer boot loader, right?) (I assume that TT Home will restore his backup to the new card) can I do everything wrong that's possible to do and then, if it stop booting, can I just insert the original SD card and get it working as it was before ?

If it's a boot-loader issue and if it is loaded to some flash then a true and final brick is possible ?

And, at last, a map question. If I'm unable to find a hash for the map I want (Iberia) would another map like South Europe be acceptable for this device ? That's the 2nd reason that I want to put a 2Gb SD in, but can the 32 Mb RAM cope with a so larger map ?

Thanks in advance.

file: /ttgo.bif