Hey folks!
I myself do not have these 137mb updates.
from reddit and the german technical support forum i got the feedback that the following steps help to solve the problem:
Go to your Documents folder:
C:\Users[YOUR USERNAME]\Documents.
Now right-click on the Heroes of the Storm folder and click on “Properties”.
In the newly opened window you have to click on the tab “Security”.
Now you have to click on “Advanced” at the bottom of the window.
A new window will open.
In this window you have to change the owner first.
To do this, click on “Change” at the top next to “Owner”.
In the text field enter your username and click on “Verify name”.Now click on “OK”.
You should now be able to set full access rights for the administrator group and your user account under “Edit”.
Once this is done, close all windows and the update / installation should work normally again.