App Lounge in e-3.6-a15 improved for me but may require Clear app storage to get a fresh start.
Settings > Apps > See all apps > App Lounge > Storage & cache > Clear storage
The above advice (and more simple advice like log out and log in again, turn off Advanced Privacy) is seen in the app itself; App Lounge > Settings page has this link showing in red as “Having troubles?” App Lounge FAQ.
If at first the problem persists be sure to take the advice to try later, like two to twelve hours later and have the phone fully charged as battery below a certain level is known to hinder or prevent download.