More info:

I tried running in debug mode via command line (in OpenLP.app) of ./OpenLP -l debug but the new OpenLP 2.4 crashes before even getting to the point of writing the log file. In terminal I see this:

MacBook-Air:MacOS user$ ./OpenLP -l debug Segmentation fault: 11 The Apple crash report shows (this is fragment)  that thread 0 crashes:  Crashed Thread:        0  Dispatch queue: com.apple.main-thread Exception Type:        EXC_BAD_ACCESS (SIGSEGV)Exception Codes:       KERN_INVALID_ADDRESS at 0x0000000000000000 VM Regions Near 0:-->     __TEXT                 0000000100000000-0000000100007000 [   28K] r-x/rwx SM=COW  /Applications/OpenLP.app/Contents/MacOS/OpenLP I ran /usr/sbin/system_profiler SPFrameworksDataType to get the installed Python & QT if that helps (although I see that this below is the same as on my other Mac where OpenLP 2.4 is working fine).     Python:       Version: 2.7.10      Obtained from: Apple      Last Modified: 03/10/15 11:59      Kind: Intel      64-Bit (Intel): Yes      Signed by: Software Signing, Apple Code Signing Certification Authority, Apple Root CA      Get Info String: Python Runtime and Library      Location: /System/Library/Frameworks/Python.framework      Private: No     QTKit:       Version: 7.7.3      Obtained from: Apple      Last Modified: 03/10/15 11:59      Kind: Intel      64-Bit (Intel): Yes      Signed by: Software Signing, Apple Code Signing Certification Authority, Apple Root CA      Get Info String: QTKit 7.7.3, Copyright 2003-2012, Apple Inc.      Location: /System/Library/Frameworks/QTKit.framework      Private: No