Ah I see, but this check=yes parameter seems only to be occur in the URL in case of NC (and maybe SAM, did not test) may be launched from the prelogin bookmarkspage. On all other implementations we have here, mostly web rewriting with direct redirection to the apps startpage, among some with bookmarkspage, this error does not occur.
But for me removing / changing check=yes to check=no does not really help. The bookmarkpage to start NC appears, but clicking the "start" button results in nothing...