Originally Posted by: mitchb 
Startup.dat goes here:
The startup.dat file is a great place to store user defined views, layers, and pen styles that you would like available for each new launch session. When ViaCAD launches, it looks for the existence of this file and if present, reads the contents into the program. To create a startup.dat file, start ViaCAD and create your specific pen styles, views, or layers. Save the file and rename to startup.dat. Move this file to the appropriate platform specific folder listed below.
Mac: 
/Applications/ViaCAD 2D 11.app/Contents/Resources/startup.dat 
...
 Thanks Mitchb.
I just tried using a startup.dat file with Sharkcad V12 but it crashes every time at startup...
Here's the crash log :
Process:               SharkCAD 12 [75732]
Path:                  /Applications/SharkCAD 12.app/Contents/MacOS/SharkCAD 12
Identifier:            com.encore.shark12esd
Version:               12.0.7 (1572)
Code Type:             X86-64 (Native)
Parent Process:        ??? [1]
Responsible:           SharkCAD 12 [75732]
User ID:               502
Date/Time:             2021-01-19 14:02:54.509 +0100
OS Version:            Mac OS X 10.15.7 (19H15)
Report Version:        12
Bridge OS Version:     4.6 (17P6610)
Anonymous UUID:        6E0D2481-3657-36C5-C2C2-4FE332C37F65
Sleep/Wake UUID:       551806B6-71EC-46B7-A1A4-DF1AAB0618A6
Time Awake Since Boot: 410000 seconds
Time Since Wake:       13000 seconds
System Integrity Protection: enabled
Crashed Thread:        0  Dispatch queue: com.apple.main-thread
Exception Type:        EXC_BAD_ACCESS (SIGSEGV)
Exception Codes:       KERN_PROTECTION_FAILURE at 0x00007ffeebdf3d98
Exception Note:        EXC_CORPSE_NOTIFY
Termination Signal:    Segmentation fault: 11
Termination Reason:    Namespace SIGNAL, Code 0xb
Terminating Process:   exc handler [75732]
VM Regions Near 0x7ffeebdf3d98:
    MALLOC_MEDIUM (reserve 00007ffd70800000-00007ffd78000000 [120.0M] rw-/rwx SM=NUL  reserved VM address space (unallocated)
--> STACK GUARD            00007ffeebdf3000-00007ffeebdf4000 [    4K] ---/rwx SM=NUL  stack guard for thread 0
    Stack                  00007ffeebdf4000-00007ffeeedf4000 [ 48.0M] rw-/rwx SM=SHM  thread 0
Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   libJS0GROUP.dylib             	0x00000001125191ef CATError::Throw(char const*, int, void*) + 1103
1   libJS0GROUP.dylib             	0x0000000112529603 CATSigHandler::Handler(int, __siginfo*, void*) + 1763
2   libsystem_platform.dylib      	0x00007fff68f815fd _sigtramp + 29