I've been having the same (or similar) issue.

Playing on Win, using Plarium Play installer from here. Issue is-

Exit game. Next attempt to play, Play client says it's updating (even if auto-update is disabled). Update never completes. Longest I've left it updating is 30mins.

Workaround. Go to Play install folder, run Uninstaller, uninstall all game files.

Download Play client again

Run installer again

Which is rather frustrating, especially as there also seems to be a memory leak which means keeping Raid running in background doesn't seem to work. Also the log viewer in the client settings takes you to a file location with an encoded/encrypted logfile, so not much use.

From experimenting, I've seen another logfile in the game folder that reports a missing .dll. Also the uninstaller leaves files behind, locked to 'raid.exe', which isn't running. So possible the game isn't exiting cleanly, confusing the installer. 

Personally, I use bluestacks a great deal. 

Try this though: My Game Won't Load: Fixes