There is a MAJOR issue with 404 page redirects not working properly in the latest version of Newscoop which also affects the Newscoop demo site and has resulted in my bounce rate reaching nearly 40 per cent after switching to a topic based navigation system and assuming 404 directs would redirect to 404.tpl
If you visit the Newscoop demo site and change the article number in the European Candidates articles from 64 to 99999 you can reproduce it, i.e.
Simpler 404s work sometimes (for example, nopagehere.html which is how most people test 404 pages)
If you look for the cause of the blank screen in the apache log it says something about zero values and article ratings, although the 404.tpl file (I'm using Quetzal) doesn't appear to call the ratings template anywhere.
My site has now been penalised by Google and lost half its Alexa rank (it has lost 500,000 places and is now at 1 million) which is what advertisers look at) so I will appreciate help from Sourcefabric (incidentally, I wrote to you requesting a quote for installing the Newscoop Paywall plugin since the fix that was promised for 4.2.2 [4.2.3] doesn't work, but nobody has written back).
Hey, 404 thing is on table now - we are looking for solution (4.2.4 will come).
About paywall and 4.2.3 - it can be used but only with limited functionality (without admin panel and configuration) - my advise is to wait for first 4.3 RC (where all is functional).