I'm giving this a go, but getting fairly regular random crashes such as the following:
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x000000017e7b400d
VM Regions Near 0x17e7b400d:
MALLOC_LARGE 000000016771c000-000000017c13a000 [330.1M] rw-/rwx SM=PRV
-->
__TEXT 0000123480000000-000012348043b000 [ 4332K] r-x/rwx SM=COW /System/Library/Extensions/AMDRadeonX4000GLDriver.bundle/Contents/MacOS/AMDRadeonX4000GLDriver
Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0 com.libraw-llc.FastRawViewer 0x0000000100187422 EXIFInfo::parseIFEntry(unsigned char const*, unsigned int, bool, unsigned int, unsigned int, unsigned int*, unsigned int) + 546
1 com.libraw-llc.FastRawViewer 0x0000000100188ace EXIFInfo::parseFromEXIFSegment(unsigned char const*, unsigned int) + 1166
2 com.libraw-llc.FastRawViewer 0x000000010016a0e4 FRV_RawProcessor::readJpegData(unsigned char*, unsigned int, int, QString const&, int, float) + 404
3 com.libraw-llc.FastRawViewer 0x000000010016bef5 FRV_RawProcessor::processFile(LibRawData_wrapper*, JpegItem*, bool, int, int, bool, QVector<float> const&) + 2053
4 com.libraw-llc.FastRawViewer 0x000000010007794c FRV_MainWindow::openFileAndDisplay(QString, LibRawData_wrapper*, JpegItem*, int, int, int) + 4780
5 com.libraw-llc.FastRawViewer 0x000000010007e960 FRV_MainWindow::openFileLibRawAndJpeg(QString, LibRawData_wrapper*, JpegItem*, int, int, int) + 48
6 com.libraw-llc.FastRawViewer 0x00000001001dc55b FRV_MainWindow::qt_static_metacall(QObject*, QMetaObject::Call, int, void**) + 2907