I found this tiny errata in the MCS UI and specifically in the text of the 'In memory' check box's hint:
Version : MAPR 5.2.2
Thanks for reporting this, Wissem. I'll put it in our bug system - though we have moved to a new MCS for MapR 6.0 and I don't know if they'll be addressing non-critical issues in the older MCS.
Retrieving data ...