Now make a log and identify the specific shows that are incorrectly mixed among the correctly scraped shows; else nobody can be bothered to look through the logfile to guess which one might have something different.
NB: Also conduct an experiment where you rename everything to exactly match thetvdb.com naming and remove all the scene flagging crap. Most of the scraping issues we see are due to lazy users not naming files correctly.
You won't succeed because the compressed .dmg format cannot be directly mounted. You can use dmg2img to convert the image file, but that won't be possible if it's still in active use with macOS. AFAIK the iPhoto's addon was written for Windows/macOS where Kodi has local access to the iPhoto's library structures.
Not possible as there is one system-wide setting. On AML devices there is also a general expectation that everything should be HW decoded as the CPU is a bit low-power for much SW use.
It won't be a CEC issue, but it could be an HDMI/EDID issue from the CEC adaptor (although those things are widely used). Remove the CEC adaptor and connect the TV direct to find out.
The same process works but I would use the opportunity to make a clean install to a new SD card instead of updating the older OE install; make a backup first (or use a clean SD card) and if necessary selectively restore bits like databases, sources and add-on settings.
Raspberry Pi has some advancedsettings tweaks applied by default that reduce the size/resolution of all the artwork in the library. You can apply the same tweak to other devices to mitigate slower scrolling performance in libraries.
Run an Ethernet cable. If you see the same issue it's something weird but probably related to video modes. If the issue is gone the issue was the wireless connection; all complaints about weird playback issues are invalid when using wireless 
It won't be an LE specific issue, but you need to make tests with Kodi Leia not Jarvis/Krypton. Even if you can prove a fault in older releases those codebases are dead (no more maintenance releases) and the fix will go into Leia.
Historically we have used a common kernel for all pi and x86 things but the team is currently split between the desire to use an LTS kernel which benefits pi hardware (a huge portion of our userbase) and to track mainline which would benefit new x86 hardware. There are benefits (and cons) to both. I personally hope we end up using LTS (4.14) for pi hardware and track mainline kernels with x86 stuff - the current 8.2 release has pi on 4.9 while x86 is on 4.11 so there is a precedent, although it's not been without issue.
Discussion on VPN use is tolerated in this forum as long as it remains focused on privacy use cases. If you drag the discussion onto the use of VPN services to bypass geoblocking (which some view as a soft form of piracy) this thread will be locked and then binned. Take that discussion to some other forum please.
There will be an 8.2.4 release in the future but there is no way we will contemplate a major kernel bump to support new Intel hardware (esp. with Intel drivers being oh-so-reliable) in a long-released branch. LE9 dev builds are the only option.
It's unlikely that LE and OE are different when it comes to RPi things .. aside from OE being outdated on software point versions.
Please provide a Kodi debug log from LE 8.2.3
Not that we heard of..
IMHO this will be a "Holy Grail" quest for two simple reasons:
a) There are probably 20+ Shenzen based manufacturers of "MXQ" boxes and they're all a teeny bit different
b) Manufacturers who stole the base design of someone else's box never publish schematics of "their" box
Good luck
Debug log .. or your problem is not our problem
Enable media "flags" in skin options and Estuary shows icons with resolution and audio/video codecs in the Library views. Most other skins do similar things. I also keep 4k and 4k UHD in different source folders so that I can exclude those sources on devices like RPi3 that cannot handle 4k media and include them on more capable boxes that do.
Although it's basically true I'm not a fan of the typical "when it's ready" Kodi answer. First alpha milestone for v18 is scheduled for April but (caveat) has already moved once and could shift again. So current guesstimate on a stable release is a few months after first alpha.
