lewiS

Can I ask to add my website to the list? https://retrolemon.co.uk/18-16-32-bit

Yes, Lotharek will be best bet in Europe.

We have just got some in stock: https://retrolemon.co.uk/8-bit-mass-storage-devices/125-avgcart.html

I am closer that you even think. I work in Greenford

Don't worry. There is a light at the end of the tunnel. Just watch this space.

I pointed Mario to tmp's shop, as he seems to be located in Germany.

https://miscretro.com/product/sio-cable-for-avgcart/

Left button on the cart. Exactly

It looks like black wire needs pushing in. Otherwise it looks good to me.

These two wires should not be connected to anything, but they should be joined. Shorting these cables tells AVG Cart that the SIO cable is present and it should use it to load ATR and CAS files. It might be that they have been not connected together, so AVG Cart loaded files through cartridge port. Which make lots of ATRs file do not load and CAS files cannot be loaded at all this way.

That might be an issue. It looks like memory failure. This could be causing before that files did not load. Do you have Sys Check cart? Do you have standard memory chips, or Lotharek's SRAM or similar?

When you load ATRs, do you hear SIO transmission beeps?

Do you have a SIO cable with your cart? https://webcache.googleusercontent.com/search?q=cache:0R6a2u3pqEMJ:https://atari8bit.net/tutorials/de-re-avgcart/+&cd=1&hl=en&ct=clnk&gl=uk

Great! Does it need firmware update?