While typing I got a crash. Here is what MAC output in the 'send report' window.
Process: vs [7366]
Path: /Applications/SlickEditPro2016.app/Contents/MacOS/vs
Identifier: com.slickedit.SlickEdit
Version: 21.0.0 (21.0.0.10)
Code Type: X86-64 (Native)
Parent Process:

[1]
Responsible: vs [7366]
User ID: 1000
Date/Time: 2016-10-06 08:37:15.919 -0600
OS Version: Mac OS X 10.11.6 (15G1004)
Report Version: 11
Anonymous UUID: 2155A868-822D-E832-1AF6-394F26A9805D
Time Awake Since Boot: 170000 seconds
System Integrity Protection: enabled
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x000000000000000d
Exception Note: EXC_CORPSE_NOTIFY
VM Regions Near 0xd:
-->
__TEXT 000000010e0af000-000000010fce9000 [ 28.2M] r-x/rwx SM=COW /Applications/SlickEditPro2016.app/Contents/MacOS/vs
Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0 libsystem_platform.dylib 0x00007fffa00a09f6 OSAtomicAdd32Barrier$VARIANT$mp + 2
1 com.slickedit.SlickEdit 0x000000010eee8ebf slickedit::SEPrivateListTagsTarget::SEPrivateListTagsTarget(slickedit::SEPrivateListTagsTarget const&) + 159
2 com.slickedit.SlickEdit 0x000000010ef0ff1e cmRCPointer<slickedit::SEPrivateListTagsTarget, true>::makeUniquePointer(bool) + 174
3 com.slickedit.SlickEdit 0x000000010eeeaf74 slickedit::SEListTagsTarget::tryWriteLock() + 20
4 com.slickedit.SlickEdit 0x000000010ef12fee slickedit::SEListTagsTargetCache::discardOldJobs() + 366
5 com.slickedit.SlickEdit 0x000000010ef1433e slickedit::SEListTagsTargetCache::addTarget(slickedit::SEListTagsTarget const&) + 190
6 com.slickedit.SlickEdit 0x000000010ef678ce SETagSetListTagsContext + 190
7 com.slickedit.SlickEdit 0x000000010eeed364 slickedit::SEListTagsTarget::insertAsynchronousTagsInContext() + 484
8 com.slickedit.SlickEdit 0x000000010eeec3bb slickedit::SEListTagsTarget::doGenericListTags() + 155
9 com.slickedit.SlickEdit 0x000000010e472f05 generic_list_tags(int, char const*, char const*, bool) + 229
10 com.slickedit.SlickEdit 0x000000010e14059f call_dllpc(int, int, namelist_t*) + 1567
11 com.slickedit.SlickEdit 0x000000010e13fe58 pcall_index_op() + 56
12 com.slickedit.SlickEdit 0x000000010e387dd1 pmethod_op() + 753
13 com.slickedit.SlickEdit 0x000000010e1429f1 run_proc(int) + 481
14 com.slickedit.SlickEdit 0x000000010e165601 run_proc_immediate2(m_s*, int, int, VSARGTYPE*, int, int) + 321
15 com.slickedit.SlickEdit 0x000000010e1653b6 run_callback_immediate(VSCALLPTR*, int, VSARGTYPE*, int) + 102
16 com.slickedit.SlickEdit 0x000000010e3fa755 se_call_callback(filewindow_t*, VSCALLPTR*, int, int, VSARGTYPE*) + 53
17 com.slickedit.SlickEdit 0x000000010e2d2ff2 vs_execute_timer_event(int) + 402
18 QtCore 0x0000000110d999c0 QObject::event(QEvent*) + 432
19 QtGui 0x0000000111076e8e QWidget::event(QEvent*) + 78
20 QtGui 0x000000011101b9dd QApplicationPrivate::notify_helper(QObject*, QEvent*) + 189
21 QtGui 0x000000011101fc38 QApplication::notify(QObject*, QEvent*) + 232
22 QtCore 0x0000000110d8546c QCoreApplication::notifyInternal(QObject*, QEvent*) + 124
23 QtGui 0x000000011101ba7c QApplicationPrivate::notify_helper(QObject*, QEvent*) + 348
24 QtGui 0x0000000110fd1a5c QDesktopWidget::resizeEvent(QResizeEvent*) + 6220
25 com.apple.CoreFoundation 0x00007fff9c6e5b94 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 20
26 com.apple.CoreFoundation 0x00007fff9c6e5823 __CFRunLoopDoTimer + 1075
27 com.apple.CoreFoundation 0x00007fff9c6e537a __CFRunLoopDoTimers + 298
28 com.apple.CoreFoundation 0x00007fff9c6dc871 __CFRunLoopRun + 1841
29 com.apple.CoreFoundation 0x00007fff9c6dbed8 CFRunLoopRunSpecific + 296
30 com.apple.HIToolbox 0x00007fff9c2fa935 RunCurrentEventLoopInMode + 235
31 com.apple.HIToolbox 0x00007fff9c2fa76f ReceiveNextEventCommon + 432
32 com.apple.HIToolbox 0x00007fff9c2fa5af _BlockUntilNextEventMatchingListInModeWithFilter + 71
33 com.apple.AppKit 0x00007fff9370ddf6 _DPSNextEvent + 1067
34 com.apple.AppKit 0x00007fff9370d226 -[NSApplication _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 454
35 com.apple.AppKit 0x00007fff93701d80 -[NSApplication run] + 682
36 QtGui 0x0000000110fd3967 QDesktopWidget::resizeEvent(QResizeEvent*) + 14167
37 QtCore 0x0000000110d84384 QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) + 68
38 QtCore 0x0000000110d84734 QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) + 324
39 QtCore 0x0000000110d86fac QCoreApplication::exec() + 188
40 com.slickedit.SlickEdit 0x000000010e0e2ba7 vmain(int, char**) + 3367
41 com.slickedit.SlickEdit 0x000000010f21538a xmain + 42
42 com.slickedit.SlickEdit 0x000000010e0fe689 main + 9
43 com.slickedit.SlickEdit 0x000000010e0b45f4 start + 52
Thread 1:: Dispatch queue: com.apple.libdispatch-manager
0 libsystem_kernel.dylib 0x00007fff89f75efa kevent_qos + 10
1 libdispatch.dylib 0x00007fff9af93165 _dispatch_mgr_invoke + 216
2 libdispatch.dylib 0x00007fff9af92dcd _dispatch_mgr_thread + 52
<Snip because it wouldn't fit in post limit. Thread 2..7 seems to be the same stack for each>
Thread 7:
0 libsystem_kernel.dylib 0x00007fff89f74db6 __psynch_cvwait + 10
1 libsystem_pthread.dylib 0x00007fff8cd6a728 _pthread_cond_wait + 767
2 com.slickedit.SlickEdit 0x000000010f2ebe4e cmWaitable::cond_wait(int) + 158
3 com.slickedit.SlickEdit 0x000000010f2ebf19 cmWaitHandle::waitOne(int) + 89
4 com.slickedit.SlickEdit 0x000000010ef1c415 slickedit::SEListTagsThread::runAsWriter() + 421
5 com.slickedit.SlickEdit 0x000000010f2eb804 cmThread::ThreadStartRoutine(void*) + 68
6 libsystem_pthread.dylib 0x00007fff8cd6999d _pthread_body + 131
7 libsystem_pthread.dylib 0x00007fff8cd6991a _pthread_start + 168
8 libsystem_pthread.dylib 0x00007fff8cd67351 thread_start + 13
Thread 8:: com.apple.NSEventThread
0 libsystem_kernel.dylib 0x00007fff89f6ef72 mach_msg_trap + 10
1 libsystem_kernel.dylib 0x00007fff89f6e3b3 mach_msg + 55
2 com.apple.CoreFoundation 0x00007fff9c6dd1c4 __CFRunLoopServiceMachPort + 212
3 com.apple.CoreFoundation 0x00007fff9c6dc68c __CFRunLoopRun + 1356
4 com.apple.CoreFoundation 0x00007fff9c6dbed8 CFRunLoopRunSpecific + 296
5 com.apple.AppKit 0x00007fff93863d95 _NSEventThread + 149
6 libsystem_pthread.dylib 0x00007fff8cd6999d _pthread_body + 131
7 libsystem_pthread.dylib 0x00007fff8cd6991a _pthread_start + 168
8 libsystem_pthread.dylib 0x00007fff8cd67351 thread_start + 13
Thread 9:
0 libsystem_kernel.dylib 0x00007fff89f74db6 __psynch_cvwait + 10
1 libsystem_pthread.dylib 0x00007fff8cd6a728 _pthread_cond_wait + 767
2 com.slickedit.SlickEdit 0x000000010f2ebdd7 cmWaitable::cond_wait(int) + 39
3 com.slickedit.SlickEdit 0x000000010f2ebf19 cmWaitHandle::waitOne(int) + 89
4 com.slickedit.SlickEdit 0x000000010f513711 fileDateThread::run() + 65
5 com.slickedit.SlickEdit 0x000000010f2eb804 cmThread::ThreadStartRoutine(void*) + 68
6 libsystem_pthread.dylib 0x00007fff8cd6999d _pthread_body + 131
7 libsystem_pthread.dylib 0x00007fff8cd6991a _pthread_start + 168
8 libsystem_pthread.dylib 0x00007fff8cd67351 thread_start + 13
Thread 0 crashed with X86 Thread State (64-bit):
rax: 0x0000000000000001 rbx: 0x0000000000000001 rcx: 0x0000000000000000 rdx: 0x66b9510066b95100
rdi: 0x0000000000000001 rsi: 0x000000000000000d rbp: 0x00007fff51b48730 rsp: 0x00007fff51b48708
r8: 0x0000000000000040 r9: 0x00007fb4f043be18 r10: 0xffffffffffffffff r11: 0x00007fb4c0700001
r12: 0x00007fb4d1458508 r13: 0x0000000000000000 r14: 0x00007fb4cf2967e8 r15: 0x00007fb4d1458538
rip: 0x00007fffa00a09f6 rfl: 0x0000000000010202 cr2: 0x000000000000000d
Logical CPU: 2
Error Code: 0x00000006
Trap Number: 14
External Modification Summary:
Calls made by other processes targeting this process:
task_for_pid: 148
thread_create: 0
thread_set_state: 0
Calls made by this process:
task_for_pid: 0
thread_create: 0
thread_set_state: 0
Calls made by all processes on this machine:
task_for_pid: 76813
thread_create: 0
thread_set_state: 0
VM Region Summary:
ReadOnly portion of Libraries: Total=363.9M resident=0K(0%) swapped_out_or_unallocated=363.9M(100%)
Writable regions: Total=1.4G written=0K(0%) resident=0K(0%) swapped_out=0K(0%) unallocated=1.4G(100%)
VIRTUAL REGION
REGION TYPE SIZE COUNT (non-coalesced)
=========== ======= =======
Accelerate.framework 256K 3
Activity Tracing 2048K 2
CG backing stores 65.2M 6
CG image 108K 12
CG shared images 336K 9
CoreAnimation 48K 8
CoreUI image data 4456K 18
CoreUI image file 192K 4
Dispatch continuations 16.0M 2
Foundation 20K 3
Kernel Alloc Once 8K 3
MALLOC 1.2G 311
MALLOC guard page 32K 7
MALLOC_LARGE (reserved) 8228K 7 reserved VM address space (unallocated)
Memory Tag 242 12K 2
OpenCL 8K 2
Process Corpse Info 2048K 2
STACK GUARD 56.1M 19
Stack 19.7M 19
VM_ALLOCATE 56K 9
__DATA 34.1M 276
__IMAGE 528K 2
__LINKEDIT 105.5M 22
__TEXT 258.8M 283
__UNICODE 552K 2
mapped file 288.5M 40
shared memory 16.3M 12
=========== ======= =======
TOTAL 2.1G 1058
TOTAL, minus reserved VM space 2.1G 1058
Model: iMac17,1, BootROM IM171.0105.B08, 4 processors, Intel Core i7, 4 GHz, 16 GB, SMC 2.34f2
Graphics: AMD Radeon R9 M395, AMD Radeon R9 M395, PCIe, 2048 MB
Memory Module: BANK 0/DIMM0, 8 GB, DDR3, 1867 MHz, 0x80AD, 0x484D54343147533642465238412D52442020
Memory Module: BANK 1/DIMM0, 8 GB, DDR3, 1867 MHz, 0x80AD, 0x484D54343147533642465238412D52442020
AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x14A), Broadcom BCM43xx 1.0 (7.21.95.175.1a6)
Bluetooth: Version 4.4.6f1 17910, 3 services, 27 devices, 1 incoming serial ports
Network Service: Ethernet, Ethernet, en0
Serial ATA Device: APPLE SSD SM0512G, 500.28 GB
USB Device: USB 3.0 Bus
USB Device: USB3.0 Hub
USB Device: Bluetooth USB Host Controller
USB Device: FaceTime HD Camera (Built-in)
USB Device: USB2.0 Hub
USB Device: Back-UPS ES 550 FW:843.K2 .D USB FW:K2
USB Device: DasKeyboard
USB Device: USB2.0 Hub
USB Device: Evoluent VerticalMouse 4
USB Device: OWC Mercury Elite-AL Pro
Thunderbolt Bus: iMac, Apple Inc., 28.1