I'm not sure if this issue is connected with new update since I can't tell when it started to behave like this.
The problem is that all modules of Avast are not working. The only thing that still works is Avast interface BUT it acts like a 'dummy' user interface. Avast doesn't save any settings under settings, doesn't launch any scans, etc.
I managed to make it work by reinstalling and cleaning BUT it only works on first start. E.g. it doesn't work on second boot.
I can schedule boot scan but upon booting it shows 'Scan 100% Complete' almost instantly which is unlikely given the scan setting was set to scan all hard drives.
Now with some info on my 'rig':
OS: Windows 7 x64
RAM: 4 GB
Also here are some pics to illustrate what I'm talking about here: