Additionnal info about the problem by Prefpan,
Process: System Preferences [249]
Path: /Applications/System Preferences.app/Contents/MacOS/System Preferences
Identifier: com.apple.systempreferences
Version: 14.0 (14.0)
Build Info: SystemPrefsApp-281000000000000~3
Code Type: X86-64 (Native)
Parent Process: ??? [1]
Responsible: System Preferences [249]
User ID: 501
PlugIn Path: /Library/PreferencePanes/VoodooPS2synapticsPane.prefPane/Contents/MacOS/VoodooPS2synapticsPane
PlugIn Identifier: com.rehabman.VoodooPS2synapticsPane
PlugIn Version: 1.0 (1.0)
Date/Time: 2015-07-19 20:07:29.903 +0200
OS Version: Mac OS X 10.10.4 (14E46)
Report Version: 11
Anonymous UUID: E4771627-E6C7-2CD6-99B7-BD9769E67D21
Time Awake Since Boot: 1500 seconds
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x0000000000000000
VM Regions Near 0:
-->
__TEXT 000000010d5d0000-000000010d5f3000 [ 140K] r-x/rwx SM=COW /Applications/System Preferences.app/Contents/MacOS/System Preferences
Application Specific Information:
com.rehabman.VoodooPS2synapticsPane v.1.0 (VoodooPS2synapticsPane)
objc[249]: GC: forcing GC OFF because OBJC_DISABLE_GC is set
Performing @selector(SlideSpeedXAction:) from sender NSSlider 0x7fb31e2245d0
Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0 com.apple.CoreFoundation 0x000000010fc90c4b CFDictionarySetValue + 43
1 com.rehabman.VoodooPS2synapticsPane 0x000000011acd0a55 0x11accf000 + 6741
2 libsystem_trace.dylib 0x0000000111714cd7 _os_activity_initiate + 75
3 com.apple.AppKit 0x000000010eb44eb1 -[NSApplication sendAction:to:from:] + 452
4 com.apple.AppKit 0x000000010eb5a946 -[NSControl sendAction:to:] + 86
5 com.apple.AppKit 0x000000010eb5a862 __26-[NSCell _sendActionFrom:]_block_invoke + 131
6 libsystem_trace.dylib 0x0000000111714cd7 _os_activity_initiate + 75
7 com.apple.AppKit 0x000000010eb5a7bf -[NSCell _sendActionFrom:] + 144
8 libsystem_trace.dylib 0x0000000111714cd7 _os_activity_initiate + 75
9 com.apple.AppKit 0x000000010eb58cb3 -[NSCell trackMouse:inRect:ofView:untilMouseUp:] + 2821
10 com.apple.AppKit 0x000000010eca4b61 -[NSSliderCell trackMouse:inRect:ofView:untilMouseUp:] + 825
11 com.apple.AppKit 0x000000010eb57366 -[NSControl mouseDown:] + 714
12 com.apple.AppKit 0x000000010f0c12dc -[NSWindow _reallySendEvent:isDelayedEvent:] + 14125
13 com.apple.AppKit 0x000000010ea50c86 -[NSWindow sendEvent:] + 470
14 com.apple.systempreferences 0x000000010d5d7b12 0x10d5d0000 + 31506
15 com.apple.AppKit 0x000000010ea4d212 -[NSApplication sendEvent:] + 2504
16 com.apple.systempreferences 0x000000010d5d6f7b 0x10d5d0000 + 28539
17 com.apple.AppKit 0x000000010e976b68 -[NSApplication run] + 711
18 com.apple.AppKit 0x000000010e8f3244 NSApplicationMain + 1832
19 libdyld.dylib 0x00000001113e65c9 start + 1
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Graphics: Intel HD Graphics 3000,, Intel HD Graphics 3000,, Built-In
Memory Module: BANK0/DIMM0, 4 GB, DDR3, 1333 MHz, Corsair, CMSO4GX3M1A1333C9
Memory Module: BANK1/DIMM1, 2 GB, DDR3, 1333 MHz, Corsair, CMSO4GX3M1A1333C9
AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x2123), Broadcom BCM43xx 1.0 (7.15.166.24.3)
Network Service: Ethernet, Ethernet, en0
PCI Card: Realtek RTL8168E/8111E PCI Express Gigabit Ethernet, Ethernet, Ethernet
Serial ATA Device: CT500BX100SSD1, 500,11 GB
Serial ATA Device: MATSHITABD-CMB UJ152
USB Device: Hub
USB Device: USB2.0 Camera
USB Device: Fingerprint Sensor
USB Device: Hub
USB Device: Ultra Fit
Thunderbolt Bus: