DA2 "All That Remains" quest bug

Hello, I'm replaying DA2 and I have problem with "All that remains" quest. I stucked at the part where you must follow the blood trail to the Dark Foundry. I talked with Gamlen and the Urchin, quest mark points the blood spot, but when I click on it nothing happens. The quest mark should move to the next bloody splat, but it doesen't happen. I tried to load ealier save, save game and quit, running around blood splat with tab pressed for highlighting. Nothing worked. Is this problem connected with killing Gascard DuPuis during the Prime Suspect quest? At my first playthrough I didn't have such problems, but I let him live.