I'm currently on the last case... and there's something completely odd with it.
Time-traveling evidence? WTF? I've just got the crystal bottle in the present from Kristoph Gavin, yet I'm able to use it in the past, presenting it to Vera Misham! Heck, there was a bottle just like it on the desktop in the studio, why could we use that one as "evidence" instead of a magic crystal bottle? The concept of discovering the truth following to different timelines is cool, but hell... using the same evidence both in the past and in the present is way, way off.
Seriously, this is the weakest game in the series, IMO. Nice upgraded graphics and cool videos, though.