Vast Studios apparently got some funding from Ontario Media Development Corporation because it gets a big credit in the opening of Nightfall Mysteries: Black Heart. On the OMDC website I could find no mention of Vast.
Here are some I quite liked, both Forgotten Kingdoms: Dream of Ruin and Forgotten Kingdoms: The Ruby Ring although I can't swear to liking Ruby Ring, which I believe is the sequel, as much as Dream of Ruin as I have only replayed Dream of Ruin recently.
I heartily recommend Dark Canvas: A Murder Exposed and Nightfall Mysteries: Black Heart. The games as a whole do not feel rushed, and particularly with regard to Black Heart but to some extent with A Murder Exposed as well, I don't feel condescended to or patronized by the developers.
I haven't finished Black Heart because, son of a gun, after some minor hair pulling I figured out how to do a clock puzzle, which was swap the numerals into the correct slots when one pair of buttons goes clockwise and swaps with one space between, and the other, counterclockwise with two spaces. I got all the way to the last two numbers which had a doable space between them. Instead of swapping them, I hit the puzzle reset button. That was a little stupid of me; nevertheless I like playing games where the overall construct and the individual puzzles show enough ingenuity that I get the impression the developers respect my intelligence. I certainly don't want to skip the puzzle after all that, so I'm giving it a rest.