Although avast! allow me to use the modified list of backup and keep AT after flashing an OTA of the ROM (without wipe), it’s NOT surving at all.
I see that SuperSu has the same feature and it’s working ok in my maguro with SlimRom 4.4.2 rooted. Slim uses a lot of CM code, maybe due to this is that option available.
I’ve found that a script could backup and save files trying to survive a ROM flash.
http://t53n.blogspot.nl/2013/01/keep-system-files-when-updating.html
Which avast! files should I add to the script in order to restore it afterwards?