I love retroarch. But i have a annoyance with your mamecore, when i run a game the game have a weird resolution (gameinfo screen for exemple presents blury lines).
What i need to configure to get correct resolutions?
You have to use MAME 2014 for now. The latest MAME core has that problem.
You can also use the mame-git core with the ‘alternate renderer’ core option, though that has some other problems.