Switching the Wayland compositor used by Kicksecure isn’t supported currently. Supporting a Wayland compositor is much more involved than supporting a window manager under X11, because the compositor is both the window manager and the display server. Of all the desktop environments in Kicksecure, LXQt was the only one light enough to be suitable for Kicksecure and that had mature enough Wayland support, and the best-supported compositor for LXQt is labwc, so that’s what we went with. (For similar reasons, switching the desktop environment entirely is also difficult.) This is likely the source of both the screen lock and keyboard layout issues.
That being said, labwc does support multiple workspaces. LXQt’s workspace switcher doesn’t work with them yet, but you can configure keyboard shortcuts for switching workspaces in ~/.config/labwc/rc.xml. See labwc.
The trackpad issue sounds like it may be a hardware problem that showed up by coincidence. We don’t do anything special to the touchpad config in Kicksecure. Hopefully a reinstall will fix it, but it sounds like you tried that without success. I’ve previously managed to fix a broken touchpad by opening the laptop, then removing and re-inserting the touchpad’s ribbon cable.