I am unable to run 1.5.2 beta 4. I get the "A purchased copy of Affinity Photo must be installed to use this beta." message, and then it quits. Version 1.5.1 is installed; I get the message whether it's running or not. iMac (27 inch, late 2012), running OS X 10.12.3.
I have not been able to determine whether my Library Panel problem has been solved in the beta version. This problem is copied below from the mac problems forum:
I cannot view the library panel on my iMac (27 inch, late 2012), running OS X 10.12.3. That is in spite of downloading a fresh copy of Affinity Photo 1.5.1 from the App Store and following your Reset instructions posted 10 December 2016. There is a View-> Studio -> Library entry, but checking/unchecking that entry has no effect. Re-starting Affinity Photo did not help.
In contrast, I can view the library panel (and install the macro pack) on my MacBook Air (13 inch, mid 2011), also running OS X 10.12.3.