I have installed the latest version of DraftSight on a MacBook running SnowLeopard, but have not been able to open it.  I have installed and used previous versions on the same system without major incident.  Below is the text of the error report compiled by the system:

Process: DraftSight [2045]Path: /Applications/DraftSight.app/Contents/MacOS/DraftSightIdentifier: com.3ds.draftsightVersion: ??? (???)Code Type: X86-64 (Native)Parent Process: launchd [101]

Date/Time: 2015-04-11 16:24:41.970 -0700OS Version: Mac OS X 10.6.8 (10K549)Report Version: 6

Interval Since Last Report: 75932 secCrashes Since Last Report: 2Per-App Crashes Since Last Report: 6Anonymous UUID: 14A08724-0AD8-4D6F-9E8E-CACEFFF987A0

Exception Type: EXC_BREAKPOINT (SIGTRAP)Exception Codes: 0x0000000000000002, 0x0000000000000000Crashed Thread: 0

Dyld Error Message: Library not loaded: /usr/lib/libc++.1.dylib Referenced from: /Applications/DraftSight.app/Contents/MacOS/../Frameworks/QtWebKitWidgets Reason: image not found

Binary Images: 0x7fff5fc00000 - 0x7fff5fc3be0f dyld 132.1 (???) /usr/lib/dyld

Model: MacBook4,1, BootROM MB41.00C1.B00, 2 processors, Intel Core 2 Duo, 2.4 GHz, 2 GB, SMC 1.31f1Graphics: Intel GMA X3100, GMA X3100, Built-In, 144 MBMemory Module: global_nameAirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x88), Broadcom BCM43xx 1.0 (5.10.131.42.4)Bluetooth: Version 2.4.5f3, 2 service, 12 devices, 1 incoming serial portsNetwork Service: AirPort, AirPort, en1Serial ATA Device: FUJITSU MHY2160BH, 149.05 GBParallel ATA Device: HL-DT-ST DVDRW GSA-S10NUSB Device: Built-in iSight, 0x05ac (Apple Inc.), 0x8501, 0xfd400000 / 2USB Device: Apple Internal Keyboard / Trackpad, 0x05ac (Apple Inc.), 0x0229, 0x5d200000 / 3USB Device: IR Receiver, 0x05ac (Apple Inc.), 0x8242, 0x5d100000 / 2USB Device: USB Receiver, 0x046d (Logitech Inc.), 0xc52b, 0x1d100000 / 2USB Device: Bluetooth USB Host Controller, 0x05ac (Apple Inc.), 0x8205, 0x1a100000 / 2