Firstly, some Q2A themes overrides default settings on qa-theme.php file. For example, Snow theme overrides it to "kama" by 37th line:
Secondly, Q2A 1.5.3 has CKEditor 3.6.4. Moono theme supports only CKEditor v4.
To sum up, lets wait for new v1.5.4 release and hope that it will have CKEditor upgraded.