Custom Installation on machine with multiple disks, demo mode hard freezes.

[SimonGreen-NZ]

I have a PC with multiple drives in it (dates from 2017) and I want to install on a specific drive. If I go to Custom Install I can open gparted and create new partitions on that device. I created a boot/esp partition, a swap partition, and a btrfs partition that was to be the root.

After saving the partitions I can exit from gparted and return to the list of drives & partitions in the installer but it is impossible to select the ones I want in order to continue. If I double click on the boot & swap partitions these seem to get a tick mark in them - though other than trial and error there was no way to know this was required - but nothing happens if I double click on the btrfs partition. Double-clicking on another randomly chosen partition on a different device got a tick, but I don't want to do that.

Indeed, since there are no instructions on how to actually select the partitions I am unsure what the installer might have done had I proceeded.

At that point I decided to go back to Demo mode hoping to find some hints. Attempting to resize the browser it launched immediately froze the entire machine and I had to hard power cycle to reboot. The hardware is nothing weird, it's a Ryzen 3700X CPU and an nVidia 4070 video card.

I'm not a total novice Linux user - I've been using Linux since kernel version 1.3 - so it is pretty frustrating falling at the first hurdle.

[SimonGreen-NZ]

Further info - if I try the installer in safe graphics mode, it appears as if when I click on one of the partitions, there is some sort of options dialog appearing UNDER the installer main window. I can see the bottom of it when I click on what should be the root partition. The main installer window cannot be moved and the dialog does not move above the main window when you click in it.

I clearly need to use that dialog - it is asking me what to do with each partition as I can see options for boot and swap, but only for the last partition (the one that should be /). But I can't see it all so I can't use it.