Just remove the ones you have and install the 4 packages from the slint repo. Don't forget to update your lilo/grub.

No, it isn't the temperatures. But do check your RAM with memtest. Freezes like these most of the times are hardware issues, unfortunately.

You could also try a newer kernel. You could try the kernel packages from slint: http://slackware.uk/slint/x86_64/slint-15.0/slint/

A few minutes is enough time for the system to cool down. Add a temperature monitor in your taskbar, so you know exactly the temperature when it hangs.

Yes, that means that the entire system freezes. Did you check what kind of temperatures you had at the time it froze?

Also, run a memory test with memtest.

If the system is actually freezing, then you won't be able to launch anything, including xkill.

BTW, I think you're looking for alt-f2, but again, if the system freezes, it won't work.

Is it the whole system that freezes, or only X? Try to open a virtual console with Ctrl-Alt-F2. Does that work ...

Ah, thanks for that! Actually the certificate was renewed, but the nginx service didn't reload for some reason. It should be back to normal now.

Yeah, that is an issue with distrowatch. Nothing we can do here. It is exactly as you described it.

That means there is something wrong with the flatpak. It should have worked no matter the locale. The package in the Salix repos does.

You could try something like:
LANG=C flatpak run io.sourceforge.pysolfc.PySolFC
I haven't tried it though.

I'm more concerned about why the salix package doesn't work for you. Do you get any error messages? It runs OK here. Make sure you have the python-pysol_cards and python-random2 packages ...

Did you try powertop and laptop-mode-tools?