I tried running one of the included games, which wanted to run the computer in a video mode that Arculator I guess doesn't support. I presume that this is basically what amounts to a crash in Arthur.
Also shown is a dialog box, which is pretty simple, representing another crash. I'm guessing it's related to memory allocation.

Here is the Note-Pad accessory, which works as you would expect.

I expected this to be a rudimentary calendar, but apparently it's a significantly less useful "diary" program.

More of the desktop accessories.

Exiting Arthur, which brings you to a command-line prompt similar to the BBC Micro.