Last night my first impression was that things were working better after the upgrade I'd just done, although I couldn't really imagine why upgrading those four particular packages would affect cursors operation. It turns out, there was no fix.
This morning, I tried to install and configure Thunderbird on that VM, and as I did, many more instances of inappropriate cursors became apparent. Here's just one example:
That resizing cursor is nowhere near a border in this listing of emails, and it illustrates the problem that still occurs in many different areas. Overall, installing Thunderbird and configuring two email accounts was very difficult because of this.
I'm no longer interested in having this VM on that laptop. It's simply not essential, nor has this been very enjoyable. Unless others here are affected by it, please don't spend any more time on it on my behalf.
Siduction Linux is working fine on two other laptops here (not VMs), one of which is my wife's. (She loves the wallpaper images that are available with Siduction, and doesn't want to experiment with any other distros.)