Now that you have CFW, maybe it could be better if you download the original version of SysUpdater (GitHub Page:
https://github.com/profi200/sysUpdater/releases ) and install it on SysNAND, then, on SysNAND, with rxTools DevMode (
YOU MUST BE SHURE THAT IS DEVMODE, recommend to download rxTools v2.5 from rxTools.net, here's the link:
http://www.rxtools.net/php/downloads.php?dl=rxTools v2.5 , then, at the end of rxTools Menu, go to DevMode Option) Launch SysUpdater, (with SD: // updates/ "MD5 HASH CHECKED N3DS/3DS Ver. 9.2 CIA Files" , Like the last time) and Press X, when it finished, again go to DevMode on SysNAND and Launch SysUpdater, but this time Press Y. If on any of these options SysUpdater installed any file, this mean that the downgrade from 10.x to 9.2 haven't installed all the files from 9.2, but with this, it must be a fully 9.2 Firmware, hope it helps you both for any problems.
If that does't work, so then, maybe the first downgrade installed some corrupted CIA's, so... you could Downgrade to 9.0, and then Update again to 9.2 (Using this SysUpdater and SysNAND DevMode ALWAYS from now on, with any Update/Downgrade you do) to Fully Restore any corrupted file during the first downgrade, this will help a lot, it's like an Official Nintendo Update. Hope this help some people!!
EDIT: IMPORTANT INFO
you should also note that it can be pasta mode
I already didn't know so much about new rxTools updates... but that's up to every user, for what I read, pasta mode have some, and maybe more disabled checks... so, DevMode from 2.5 works perfect, if more experienced user recommend pasta mode, it's ok, but as ALWAYS, TRY EVERYTHING AT YOUR OWN RISK!
pasta mode is what dev mode is called in newer rxtools builds.