The first one is from
Scratches (it's located on the second floor, right next to the Cthulhu painting, which was also posted in this thread several years ago, if I remember correctly.) Drawing a blank on the second one.
As a side note, I did get an e-mail response last month from Jonathan Boakes about the art in The Lost Crown. He confirmed that most of the paintings appearing in TLC are by German painter Caspar David Friedrich (1774 - 1840).
The ones previously posted by me were
Sunset (Brothers), circa 1830 -1835 and
The Tree of Crows, circa 1822.
JB was actually worried that his German fans would be furious that he borrowed so many of Friedrich's works! Jonathan was also not surprised that Friedrich's works also appeared in other adventure games, these two in particular were likely chosen by game developers for their "creepy and strong graphical quality".