Identifying the people
Looking at the framed embroidery on the wall of the room, this is the Dandelion room. And according to the ledger downstairs, the man in the Dandelion room is named Willard Wright.
The watch may suggest otherwise, but given the dialog of the minstrel, it appears that the victim won the watch from the minstrel over a game of cards.
The man in the left window
Judging by the note on his person, he seems to be in the need to lie low. Perhaps he's a wanted man? Curiously, there is a wanted poster downstairs with his face on it. The poster gives his name as Robert Redruth.
The man in the right window
He is carrying an alarm rattle stating that his name is Henry Parker.
The left man at the card table
Going by the dialog between this man and the woman next to him, his name is John. The score card for the card game has a J.B.. After matching up the other names beginning with B, one name from the chalk board beginning with B remains, Breage.
The woman at the card table
She is carrying a letter addressed to Annie. The score card for the card game has an A.G.. The chalkboard says that a Green has a tab of 4 glasses of wine. Since there is no other name beginning with G, her name has to be Annie Green.
The right man at the card table
With the other participants in the current game already identified, that leaves A.B. on the score card. Conveniently, there is an Ash Blair listed in the lodger.
The poster on the wall gives his name as Evans. The score card for the card game has an M.E. and there is only one name beginning with M, Maurice. His name is therefore Maurice Evans. This is further supported by him thinking about gambling away something precious, and the victim having a fine watch with the name Maurice engraved on it, the item that was lost gambling.
He is carrying a letter addressed to Oscar Boyton, which is his name.
The card game scorecard
There is only one M.E., Maurice Evans. Likewise, there is only one O.B., Oscar Boyton, one A.B., Ash Blair and only one W.W., Willard Wright.
This leaves J.B. and A.G.. John is the only name beginning with J. However B is a bit ambiguous. With all the other B names resolved, Breage is the one that remains.
Similar logic applies to A.G, while there is another name beginning with A, that one is already identified as belonging to someone else. This is Annie Green.
Filling out the scroll
The first paragraph is stating whose room was entered and how. The simplest answer is that it was the victim's room. Given that the victim is dead, the same person who entered the room also killed him.
As for the method of entry, the door to the room is locked and the window is too far a drop and guarded. There is however a trapdoor in the ceiling, allowing access between the two rooms.
With the other room showing no signs of an exit route besides its door, only the occupant of the left room could have used the trapdoor. The framed embroidery on the wall suggests that the left room is the Forget-me-not room. According to the ledger, that room is occupied by Ash Blair.
The second paragraph pertains to who were playing cards while the murder occurred. Since the victim was in the first round and the third round is still ongoing, the murder had to have been happened during the second round. Going by the score card, A.G., J.B. and O.B were the players for that round.
The third paragraph formally states who the victim is and what the murder weapon was. There is a lot of weapons around, but the murderer is still carrying the murder weapon on his person.