A 'permanent' circuit shouldn't need concrete barriers lining the track edge. Apart from disqualifying the venue from holding international motorcycle races (unless the Koreans don't care about rider safety in their domestic racing), the barriers will only damage cars and hurt drivers.
It makes a mockery of Herman Tilke's comment "For example, nowadays you need the run-off areas. The FIA will not accept tracks without the run-off." (
http://www.autosport.com/news/report.php/id/86442).
The layout is basically three 'squirts' and a lot of 'wiggles', to paraphrase late, great Australian touring car driver Ian 'Pete' Geoghegan (he described the original Calder Park circuit in Melbourne as "two squirts and a wiggle").
Even allowing for the video 'flattening' effect, the elevation changes look insignificant.
It's just another reason why new F1 circuit designers should consult F1 drivers and not a former used car trader.