WanWizard

As you described the complexity, that (now) seems like a bad idea to me.

You wrote before that the current setup is to show a list of options when you first press the EPG or INFO button. Which is fine by me. And then that you wanted to change it. So I ask "why"?

The crash happens in flushChanges(), when accessing a Python datastructure. Unfortunately there isn't more info in that crash log...

That confuses me.

The index is orbital position, which hasn't changed, so when you opened the tuner configuration menu, it should have already said "A / B".

But you wrote:

I re-configured Tuner A & B (B equal to A) by allocating 5W-A/B now visible in the list of satellites to the same LNB previously allocated to 5W-A

which indicates that that didn't happen.

You didn't previously use a third-party satellites.xml which has other orbital positions as index? If so, your entire channel list might now be off...

Lets wait and see if the TS can provide more details on what exactly the situation is and what he was doing.