Steps to reproduce:
1. Download project from the link in the description
2. Run Unity with -enableUnityConnectPrefs -cloudEnvironment staging -debugallocator -enableCollabEventLogs arguments

Result: Editor crashes on "Preparing your project for Collaborate" dialog

Reproducible with: 2017.1.0b3

Callstack:
> Unity.exe!art_search(struct art_tree ,char ,int) Unknown
Unity.exe!CollabCache::Search(class core::basic_string<char,class core::StringStorageDefault<char> > const &) Unknown
Unity.exe!CollabAssets::Initialize(class core::basic_string<char,class core::StringStorageDefault<char> > const &,bool,bool,long) Unknown
Unity.exe!CollabAssets::Initialize(class core::basic_string<char,class core::StringStorageDefault<char> > const &,long) Unknown
Unity.exe!Collab::InitCollabAsset(class core::basic_string<char,class core::StringStorageDefault<char> > const &) Unknown
Unity.exe!Collab::InitAssets(bool,bool) Unknown
Unity.exe!Collab::Tick(void) Unknown
Unity.exe!Application::TickTimer(void) Unknown
Unity.exe!MainMessageLoop() Unknown
Unity.exe!WinMain() Unknown
Unity.exe!__tmainCRTStartup() Unknown
kernel32.dll!00007ffc3bc32774() Unknown
ntdll.dll!00007ffc3dad0d61() Unknown