I used angular-cli@1.0.0-beta.10 before and now I updated to angular-cli@webpack beta.11. After a lot of custom changes I got it to work.
The only thing is that now
What finally helped me was to add an additional / (forward slash) after webpack:///, so that there are 4 instead of 3. By default there were 3 forward slashes
The remote URL points to the same parent directory as on the left except the webpack://// schema.
Also you don't need to enable the TS compiler as often suggested.