I know this has been posted before, but I tried the suggestions in those threads and still can't see video previews.
It just displays the still pictures instead of the videos. Files are in the correct directories and named like the roms (they're the EmuMovies set), and the videos DO play in Media Player, so I have the correct codec(s) installed. The layout file DOES have artwork #1 and #2 present, so that bug is accounted for as well.
Mamewah file version is 1.6.0.2
Here's the relevant part of my mame.ini:
### Artwork Settings ###
artwork_image_paths auto:[emuexepath]\snap;[emuexepath]\titles;[emuexepath]\marquee;[emuexepath]\control;[emuexepath]\cabinet;[emuexepath]\flyers;[emuexepath]\boxart;[emuexepath]\cart;[emuexepath]\art9;[emuexepath]\art10
movie_preview_path C:\Program Files\MAME\previews
movie_artwork_no 1
enable_fuzzy_search 0
history_dat_file
history_dat_artwork_no 2