I have explained this type of error/glitch/bug many times, but you may have missed it, so I will go through the motions once again, but, before I do, I want you to try one thing, before you log into Dash open task manager, when you click on the shortcut to Dash are there several instances of casino.exe running simultaneously?. If so click on end process until there is just one.
Try this 1st, then we will try some other stuff.
This is not, I repeat not, a problem their end.
I have seen this often, and usually after I have experienced problems. It seems to be a bug when you exit a casino. Although it closes as expected on the desktop, for some reason the task does not unload as it should, and continues idling in the background, often holding on to a considerable amount of RAM. When starting another casino, it seems that sometimes this creates a conflict, and it crashes.
I have also had problems where the lobby will crash and get closed by the OS, but the game in play carries on running as though nothing has happened. The lobby tab also vanishes. When the game is closed, there is no lobby to return to, and the whole casino exits.
GNUF in particular sometimes stops responding when exiting a game, rather than returning to the lobby.
This all started when the update that allows games to run in separate windows, rather than tabs, came along. It seems that in order to support this, games now launch as a distinct task, rather than as part of the main casino task, which now appears as "casinolobby.exe", with each game having it's own instance of "casinogame.exe" running. It does not matter that players have not activated the games in separate windows feature, the new structure is still used for launching the tasks.
Such a major change often corrupts the file structure of the MGS common cache, which needs a full clean up and reinstall from scratch to cure. This gets rid of all earlier versions of any .dll and other game files, and ensures only those for the new lobby are there.
It would be worth waiting for 32Red to confirm that the bug has been fixed before doing this, as otherwise you may simply reinstall a duff file.
Doing this will cause you to download over 10Gig through your internet connection in a relatively short space of time, which is why it can be such a problem having to do this too often. This will blow most caps on budget ISP products, and can result in throttling even on "unlimited" contracts like Virgin Media.