Reproduced the crash. Folded up and blueprinted the pattern, then froze the helices one at a time. Moved both of them successfully for a little while but finally when snugging up the core the last drag sequence (double-click unfrozen end segment of helix then left click-hold-and-drag) crashed immediately. Logs (mac and Foldit) and script log attached.
Last thing that happened from foldit log:
delta_score: 0
Playing sound: 4
***** STARTING THREAD ActionLocalMinimizePull
Excerpt of mac crashlog:
Thread 10:
0 game_library.dylib 0x02fc41e2 std::__1::enable_if<__is_forward_iterator<char*>::value, void>::type std::__1::basic_string<char, std::__1::char_traits, std::__1::allocator >::__init<char*>(char*, char*) + 98
1 game_library.dylib 0x02fd015c std::__1::basic_stringbuf<char, std::__1::char_traits, std::__1::allocator >::str() const + 108
2 game_library.dylib 0x007dee46 basic::basic_otstream<char, std::__1::char_traits >::basic_tstringbuf<char, std::__1::char_traits >::sync() + 44
3 game_library.dylib 0x0321f3a0 std::__1::basic_ostream<char, std::__1::char_traits >::flush() + 64
4 game_library.dylib 0x00b09e2b core::conformation::symmetry::SymmetricConformation::replace_residue(unsigned long, core::conformation::Residue const&, bool) + 185
5 game_library.dylib 0x00c23c32 core::pose::Pose::replace_residue(unsigned long, core::conformation::Residue const&, bool) + 44
6 game_library.dylib 0x02fa15fb interactive::util::copy_backbone(core::pose::Pose&, core::pose::Pose const&, unsigned long, unsigned long, unsigned long) + 682
7 game_library.dylib 0x02c8165c interactive::application::actions::cart::PoseLoopThreadActionCart::update_centroid_pose(boost::shared_ptr) + 364
8 game_library.dylib 0x02c72a4a interactive::application::actions::cart::ActionCartPull::thread_body_loop_unlocked(core::pose::Pose&) + 290
9 game_library.dylib 0x02c7fa01 interactive::application::actions::cart::PoseLoopThreadActionCart::on_thread_run() + 4669
10 game_library.dylib 0x02dc0f66 boost::detail::function::void_function_obj_invoker0<boost::_bi::bind_t<void, boost::_mfi::mf0<void, interactive::application::shared::ToolActionThreaded>, boost::_bi::list1<boost::_bi::value<interactive::application::shared::ToolActionThreaded*> > >, void>::invoke(boost::detail::function::function_buffer&) + 32
11 game_library.dylib 0x02f7c103 boost::function0::operator()() const + 35
12 game_library.dylib 0x02f7a923 interactive::util::Thread::operator()() + 45
13 game_library.dylib 0x02f7aae5 interactive::util::Thread::thread_entry_func() + 31
14 game_library.dylib 0x02f7a741 interactive::util::Thread::pthread_startup_helper(void*) + 17
15 libsystem_pthread.dylib 0xa1734073 _pthread_body + 184
16 libsystem_pthread.dylib 0xa1733fbb _pthread_start + 243
17 libsystem_pthread.dylib 0xa1733876 thread_start + 34
Thread 0 crashed with X86 Thread State (32-bit):
eax: 0x1fbec000 ebx: 0x70b00000 ecx: 0x20c45f30 edx: 0x00000000
edi: 0x0c705221 esi: 0x7c1ab2f1 ebp: 0xbff30a68 esp: 0xbff30a50
ss: 0x00000023 efl: 0x00010202 eip: 0x02fc41e2 cs: 0x0000001b
ds: 0x00000023 es: 0x00000023 fs: 0x00000000 gs: 0x0000000f
cr2: 0x70b00000
Logical CPU: 2
Error Code: 0x00000004
Trap Number: 14
System log from around the time of the crash: (look at italicized text)
May 6 09:19:17 Kathleens-iMac com.apple.xpc.launchd[1] (com.apple.imfoundation.IMRemoteURLConnectionAgent): Unknown key for integer: _DirtyJetsamMemoryLimit
May 6 09:26:37 Kathleens-iMac com.apple.xpc.launchd[1] (com.apple.quicklook[1223]): Endpoint has been activated through legacy launch(3) APIs. Please switch to XPC or bootstrap_check_in(): com.apple.quicklook
May 6 09:26:47 Kathleens-iMac com.apple.xpc.launchd[1] (edu.washington.foldit.3412[1209]): Service exited due to signal: Segmentation fault: 11 sent by exc handler[0]
May 6 09:26:47 Kathleens-iMac com.apple.xpc.launchd[1] (com.apple.ReportCrash[1224]): Endpoint has been activated through legacy launch(3) APIs. Please switch to XPC or bootstrap_check_in(): com.apple.ReportCrash
May 6 09:27:08 Kathleens-iMac com.apple.xpc.launchd[1] (com.apple.imfoundation.IMRemoteURLConnectionAgent): Unknown key for integer: _DirtyJetsamMemoryLimit
May 6 09:27:09 — last message repeated 1 time —
May 6 09:27:09 Kathleens-iMac com.apple.appkit.xpc.openAndSavePanelService[1245]: assertion failed: 16E195: libxpc.dylib + 74307 [ABC45890-DA23-3A4A-B50B-1384BD4CBBDF]: 0x89
May 6 09:27:31 Kathleens-iMac com.apple.xpc.launchd[1] (com.apple.imfoundation.IMRemoteURLConnectionAgent): Unknown key for integer: _DirtyJetsamMemoryLimit
May 6 09:27:51 Kathleens-iMac DocumentPopoverViewService[1254]: BUG in libdispatch client: kevent[EVFILT_MACHPORT] monitored resource vanished before the source cancel handler was invoked
May 6 09:28:42 Kathleens-iMac syslogd[49]: ASL Sender Statistics
May 6 09:28:53 Kathleens-iMac LogViewer[1257]: assertion failed: 16E195: libxpc.dylib + 74307 [ABC45890-DA23-3A4A-B50B-1384BD4CBBDF]: 0x89
May 6 09:29:11 Kathleens-iMac LogViewer[1257]: BUG in libdispatch client: kevent[EVFILT_MACHPORT] monitored resource vanished before the source cancel handler was invoked