PetrolDave

Reformat it to FAT32 but select the option to make the cluster size 4KB instead of default - that will stop the many small files wasting so much space.

I keep doing that too

A few years ago when I was working for an automotive consultancy one of the development engineers at Ford Research Dunton expressed the opinion that he would never buy any new model in its first year as, in his opinion, new models were usually rushed to market before they had the bugs fixed.

A relative put Redex into their Octavia III and got plagued by random O2 sensor problems which went away when they stopped adding the Redex.

Any sign of the Amundsen MIB1 2021 maps yet?

VAG seem to change their mind seemingly at random depending on year of manufacture and market - for example on my 2007 Audi the media would stay on until I removed the key but on my 2015 Skoda it goes off when I turn the ignition off; and on US websites many Audi owners complain that even on earlier model years it behaves this way instead of the way my Audi did. So it seems model year, market, and how the VAG software guys "felt" are factors that determine when the media goes off

Same here.

Are you 100% sure that your 2008 Octavia PD170 has a DPF?

My 2p worth .... service - yes. cambelt - no, too risky for me to try without the proper tools. waterpump - probably but only IF it can be done without disturbing the cambelt.

Some cars have been held in a lot for well OVER a year - when production exceeds demand it's happened. Have you not seen the pictures of a large airfield near Huntingdon absolutely full of unregistered cars a few years ago? Conversely you can get a 2017 Model Year car on a 16 plate - because Model Year changes in early Summer, so a newly built car registered in August can be for the next Model Year.

If your sat nav has a USB connector on it then it will NOT need 12V (no USB connectors have ever used 12V), all you need is a USB-C to USB lead.

Looks like you have some fuse checking and wire tracing to do - don't ignore the 49493 no communication with instrument cluster as this plays an important role in the immobiliser to ECU communication.

Not MADE, first registered - there have been many examples over the years of cars sitting in a holding lot for months, sometimes over a year, before being registered.

If you have a spare key, try that. Fault finding this over the internet isn't possible, you'll need to get a fault code scan done (I always suggest using VCDS but other diagnostic tools are available) which will give information about why the immobiliser is unhappy.

Starting then turning off after a few seconds = immobiliser.

If you use micro SD cards how about this USB-C to micro SD adapter from Amazon? USB-C to micro SD adapter

It's a trunk if you speak American English, otherwise it's a boot. BTW there is a tweak to delay the boot locking, see Enable boot lid lock delay - it's saved me from locking the keys in the boot a couple of times!

What stuff did you do that you should not have? Some things can only be reset by a factory connection (e.g. where a configuration file has been deleted/overwritten) but others can be sorted out by reversing the coding/adaptation changes and possibly running some recalibration functions - to know which applies here we need to know exactly what you did.

Why do you think it's still picking up TMC when TMC is clearly crossed out?

But TMC is crossed out, which suggest it isn't picking up TMC? Don't confuse TA/TP with TMC. What changed on the car just before TMC stopped working?

At a guess, because the tailgate is not fully latched closed so the operation (or lack of) of the hall sensor is not as important. Either way, that's the only fault being shown so you'll need to fix that.

Maybe that's because nobody here has any feedback? ... because we don't agree with the concept of "ambulance chasing"?

Like it says "Hall sensor in motor 2 for rear hatch Signal error" so either the wiring to the sensor has a break, the hall sensor has been knocked/moved or the hall sensor is faulty. Time to find where motor 2 is in the rear hatch and do some basic fault finding now that OBD11 has pointed you to the problem area.

Is your FM station reception OK, and with good RDS (station information) OK? TMC is transmitted using extra signalling on some FM radio transmissions.

If you haven't suffered any financial loss then you aren't entitled to any compensation for the loss that you haven't had - to claim otherwise could be taken as fraud. When have any lawyers been trustworthy?