I deleted approximately 40 applications across 2 devices, an HP laptop and an AMD/ASRock desktop, in batches of 5-6 apps at a time. I decided then to a large amount at once and after reboot I noticed they were still listed in uninstaller. Some can still be found in the directory listed, although it appears some of the uninstall was complete.
The apps in question are all Microsoft store apps, and I did delete the store in the large batch. Reinstalling the store through the Xbox app did not help unfortunately. I've ran "Fix information" until it confirms it is all fixed, and when I select "Show Data" on the problem Store apps, they follow a similar pattern. They all show (+ or - 1) a total of 7 pieces of data, 1 file or folder, and 6 registry keys remain. However, it does appear that more than that remains, as the directories of the Content and Teams store apps (in C:\Windows\SystemApps and C:\Program Files\WindowApps\ respectiverly) show more than what Uninstalr is reporting.
I've tried rebooting numerous times, and granted the local Administrator group ownership and Full control of the directories in question, but no luck. I will reinstall later today when I return.
Still an awesome product - your work is appreciated.