KB42727: Calendar selector month cannot be changed when user creates a date condition on a new custom group using the Custom Group Editor in MicroStrategy Web.

SYMPTOM:
In Strategy Web, the Custom Group Editor allows users to create custom groups without going through the Strategy Desveloper interface. However, if the custom group is based on an attribute from of type Date, when using the condition "Between" and using the calendar selector to change the month, nothing happens; the month cannot be changed, like shown below:
 

 
Notice from the image above that the calendar picker has arrows to navigate to other months, however they do not react to the users' clicks. 
 
CAUSE:
This is a known issue in Strategy Web 9.4.1 - 10.3.
 
ACTION:
This issue has been addressed in Strategy Web 10.4. Upgrade to take advantage of the fix.
 
WORKAROUND:
Create the custom group through Strategy Developer for custom groups that rely on date conditions.
KB42727