Ok I gather that this was written mainly by J. Chapman Miske, based on another dream that Lovecraft had.
But reading it is confusing. It starts talking about Morgan and what he wrote. Morgan then writes that his name is Howard Phillips, he lives at 66 College Street in Providence, and had a dream he can't wake from. So I guess the implication is that HPL is dreaming that he's Morgan. Or other people call this mystery dream character Morgan. I'm confused!
Much of the text that follows reads as typical Lovecraft. Indeed comparing Lovecraft's original letter recording his dream in with the published Miske short story shows much of Lovecraft's text almost totally unchanged.
The account of the narrator (HPL? / Morgan?) making a difficult journey is very imaginative, and reminiscent of HPL's accounts of journeys by Randolph Carter and others.
I really liked the image of an abandoned trolley car, that the narrator gets into, only to encounter - night after night after night - a terrifying image of its driver and conductor. I was reminded here a bit of Ray Bradbury's Dandelion Wine stories which frequently feature trolley cars in small town America.
And tentacles! Or at least one tentacle, blood red too. For all his reputation, Lovecraft's stories contain remarkably few tentacles.
So yes, confusion aside - i.e. I don't think Miske exactly made this easier to read - I rather like this one.