Mac Outlook 2011 Version 14.5.2

I recently updated my iMac to OS X Yosemite Version 10.10.4.  Since that time my Outlook has been "dumping" all emails more than three days old without any input from me.  The lost emails are not in the deleted items folder, they are just gone...  I have not reverted to the previous OS X version of Yosemite but I have reset all of my Outlook settings to default without effect.  Finally, I am using iCloud (20Gig) for storage.  

Questions - (1) Are there known incompatibilities between Mac Outlook 2011 Version 14.5.2 and Yosemite 10.10.4?  

(2) Is there a setting in Outlook that limits the time incoming emails can be stored?