Download the client here: http://www.alta.hk/client/download.php?game=DS
Chose - Google 雲端海外下載點
or full patched client (7/18/2015) here.
When installing a patch you must follow that. Don`t forget to choose your dragon slayer game folder C:\Alta\DSOnline
After that we need to wait for the window to disappear. If the client still patching it means it checking files/downloaded some files that not in patch/downloading bin.
Can`t enter/update? look here