I compiled qt5ct on my Devuan 2 box with the docs on the link. It works for me.

Indeed. I have a separate partition for /tmp in some boxes.

Of course. In my experience I've never go to more than 10 GB. And 4.3 is very similar to my standard install of a full desktop.

May be just a matter of taste. I think that it is powerful and simple. (I always use the "Expert install").

No, it is not experimental. It is old code by now. It get new options, but I've been using it (with Debian and Devuan) more than 10 years. 15? No glitchs. Some times hardware has errors and they get up to the installer.

Good idea, IMHO. Please also consider something like that:
https://www.amazon.com/dp/B00L3W4G1I
I have two of them in my box and they are very useful to make backups on standard spinning drives.

You mean 500 GB, right?

This is for sure. I learned the hard way how important is doing regular backups.

Wise move, IMHO. Now, I have four backups and rotate them weekly.

Money is a big constraint, of course. One of the zillion things I like with free software is that we can do a better use of the resources, money and hardware.

Good luck

No, in Beowulf no.

I use an old trick for that:

cp /home/user/.Xauthority /root/

It seems to me that the low level staff of eth0 is right in your two systems. The relevant line of dmesg being:

r8169 0000:04:00.1 eth0: Link is Up - 1Gbps/Full - flow control rx/tx

So, I think that the difference could be the logical configurations. Do you have installed a network manager (network-manager, wicd,...)? In any case, please post your /etc/network/interfaces

Usually we need to know the gore details. Let's start for posting the result of running the order dmesg.

Could you please post the result of the command dmesg?

Agreed. But it is strange that cfdisk can see them.

Very unlikely, IMHO. I've deal hundreds of times with setups like yours and your issue is new to me.

I'm scratching my head right now. But I'm confident that a solution eventually came up from this forum.

Could we see the exact command you tried and the error you got? I mean, from the command line.

May be there are other posibilities better than mine, but I share what I do: using netinstall.iso I choose minimal system and then install only the packages I know that I need, almost one by one at first (consuming task, but I'm used to do it and now I've some bash scripts). This way, you can see if pulseaudio try to get installed and when.

Two pieces of advice: do not install recommended packages and use apulse instead of pulseaudio when needed (I use it for Firefox).