Afaik for Application Roles to take place, user should re-login -- Roles are assigned on login. So -- no need to restart the web application, but user should log out and login again.
And yes, Application Roles is a great tool to minimize privileges that are given to the user directly
a) Try setting error page as %CSP.Error.cls for this web application, then errors are shown on the page itself, instead of being logged
b) Reproduce the error with ^%ISCLOG enabled:
set ^%ISCLOG = 3
Reproduce the error quickly.
set ^%ISCLOG = 0
Check for errors in ^%ISCLOG:
Also, you can create calculated dimension member and sort members by PROPERTIES("KEY") using following expression:
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