PCLinuxOS KDE Darkstar - Commentary, cont.

I decided to get a start on configuring this distro tonight. It's been nearly uneventful, except for one issue. Every time I start the VM, or reboot, the display resolution setting returns to its smaller default size. I thought it might improve things if I were to install the VBox guest additions, but that just made things worse. Now, if I try to resize the VM by dragging the bottom right corner, the image turns black and there's nothing more I can do with it.
Before this happened, I managed to do an apt update and upgrade, installed micro, nfs-utils, Thunderbird, and Vivaldi, all without a problem. Its repository is apparently very well stocked. Given that apt is its package manager, I'm assuming this is a Devian- or Ubuntu-based distribution.
So, tomorrow I'm going to try to figure out the resizing issue. I wish I'd taken a snapshot before all this happened, but hindsight is always 20/20, I guess. Now, I'm really going to retire for tonight.