Sandbox does not activated when I start program from interface.

Avast Free Antivirus / Premium Security
1

Tools → Sandbox → Run program

When I select a program and click open (or double click), program is starting without sandbox.
All good if I use sandbox from context menu (right click at program).

This issue appears in Windows 8.1 x64 (Avast Premier).
In Windows XP SP3 all good (Avast IS).

2

Addition:
This issue appears when program located in C:\Windows\System32 (calc.exe, notepad.exe)

All good if program located in Desktop folder.

Are there exist some exception rules for program location?

3

Addition:
On 64-bit system this issue appears when program located in C:\Windows\System32 (calc.exe, notepad.exe).
But there is no issue when I use same program from C:\Windows\SysWOW64 (calc.exe, notepad.exe).

4

I had also noticed that for a temporary solution go to any file that you want to run in avast sandbox right click the file that you want and choose run in sandbox.