I remembered that in the beginning it was possible to link images and audio files from the internet in MasterPlan. But in the current version only locally saved images and audio files work. I noticed this through your Twitter entry for #Inktober, because I tried to collect some inspirations from the internet in one single MasterPlan. It would be sad, if this would not work anymore, because it is very cumbersome to save all pictures on your hard disk, especially if you just want to save an inspiration for a quick idea.
You can also see this in your help_manual.plan. The "bartender.png" from your homepage is also not shown there anymore, which is a pity, because I like the picture ;)
By the way, I use Windows 10 Pro, if it has anything to do with it.
So this is less a bug than a lost feature? xD
Your last stream was great as always, hope for more!
Have a good time.