Switch between Xcode 6 and Xcode 4.5 - ios

Question

Using OS X Yosemite
Removed Xcode6, and installed Xcode 4.5 following this guide:
http://iosdevelopertips.com/xcode/install-multiple-versions-of-xcode.html
Installed Xcode 4.5 under a different folder and used the command "sudo xcode-select --switch /Applications/Xcode4.5/Xcode.app" (in terminal) to switch to the new Xcode4.5 version (from guide above).
Got an error message stating an incompatible "MobileDevice.Framework" was installed on first launch. Followed this guide to fix that issue: Xcode 4.4.1 does not work properly under OSX Mavericks
After running command: "sudo rm -rf /System/Library/PrivateFrameworks/MobileDevice.framework" from the stack overflow issue above, I am getting another error that I have not been able to resolve after many days of research:
Process: Xcode [2422]
Path: /Applications/Xcode4.5.2/Xcode.app/Contents/MacOS/Xcode
Identifier: com.apple.dt.Xcode
Version: 4.5.2 (1847)
Build Info: IDEApplication-1847000000000000~5
Code Type: X86-64 (Native)
Parent Process: ??? [1]
Responsible: Xcode [2422]
User ID: 501
Date/Time: 2014-12-29 13:36:32.026 -0500
OS Version: Mac OS X 10.10.1 (14B25)
Report Version: 11
Anonymous UUID: 1076DD40-2DC4-A657-02AE-90EA3278917B
Time Awake Since Boot: 4200 seconds
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Application Specific Information:
ProductBuildVersion: 4G2008a
UNCAUGHT EXCEPTION (NSInternalInconsistencyException): Extension Xcode.Device.iPhone class 'DVTiPhoneLocator' not found for required key 'locatorClass'
UserInfo: {
DVTExtensionClassNameErrorKey = DVTiPhoneLocator;
DVTExtensionIdentifierErrorKey = "Xcode.Device.iPhone";
DVTPlugInExecutablePathErrorKey = "/Applications/Xcode4.5.2/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/Library/Xcode/PrivatePlugIns/IDEiPhoneSupport.ideplugin";
DVTPlugInIdentifierErrorKey = "com.apple.dt.IDE.IDEiPhoneSupport";
}
Hints: None
Backtrace:
0 0x00007fff85859634 __exceptionPreprocess (in CoreFoundation)
1 0x00007fff8b2ac6de objc_exception_throw (in libobjc.A.dylib)
2 0x0000000109c1eff1 -[DVTExtension _adjustClassAttribute:forKey:inParameterData:] (in DVTFoundation)
3 0x0000000109c1ec56 -[DVTExtension _adjustClassReferencesInParameterData:usingSchema:] (in DVTFoundation)
4 0x0000000109c7554f -[DVTExtension _fireExtensionFault:] (in DVTFoundation)
5 0x0000000109c75110 __63-[DVTExtension _valueForKey:inParameterData:usingSchema:error:]_block_invoke_0 (in DVTFoundation)
6 0x0000000109c9c446 __DVTDispatchSync_block_invoke_0 (in DVTFoundation)
7 0x00007fff8b210c13 _dispatch_client_callout (in libdispatch.dylib)
8 0x00007fff8b211e5e _dispatch_barrier_sync_f_invoke (in libdispatch.dylib)
9 0x0000000109c9c263 DVTDispatchSync (in DVTFoundation)
10 0x0000000109c9c077 DVTSyncPerformBlock (in DVTFoundation)
11 0x0000000109bf917d -[DVTDispatchLock performLockedBlock:] (in DVTFoundation)
12 0x0000000109c75007 -[DVTExtension _valueForKey:inParameterData:usingSchema:error:] (in DVTFoundation)
13 0x0000000109c1e40d -[DVTExtension valueForKey:] (in DVTFoundation)
14 0x0000000109c23c03 +[DVTDevice _knownDeviceLocators] (in DVTFoundation)
15 0x0000000109c237bc -[DVTDeviceManager startLocating] (in DVTFoundation)
16 0x000000010a50d3d3 __IDEInitialize_block_invoke_0 (in IDEFoundation)
17 0x000000010a50d986 IDESetSafeToLoadMobileDevice (in IDEFoundation)
18 0x000000010a81f6e3 -[IDEWelcomeWindowController _showFirstLaunchExperienceIfAppropriate] (in IDEKit)
19 0x000000010a81f604 -[IDEWelcomeWindowController openWelcomeWindowAfterFirstLaunchExperienceIfAppropriate:] (in IDEKit)
20 0x000000010a81f56e -[IDEApplicationController applicationOpenUntitledFile:] (in IDEKit)
21 0x00007fff8dcdfa5a -[NSApplication _doOpenUntitled] (in AppKit)
22 0x00007fff8dc18b91 __58-[NSApplication(NSAppleEventHandling) _handleAEOpenEvent:]_block_invoke (in AppKit)
23 0x00007fff8e33e5b0 __95-[NSPersistentUIManager restoreAllPersistentStateRegisteringAsReadyWhenDone:completionHandler:]_block_invoke557 (in AppKit)
24 0x00007fff8df22389 __97-[NSDocumentController(NSInternal) _autoreopenDocumentsIgnoringExpendable:withCompletionHandler:]_block_invoke_3 (in AppKit)
25 0x00007fff8df21d81 -[NSDocumentController(NSInternal) _autoreopenDocumentsIgnoringExpendable:withCompletionHandler:] (in AppKit)
26 0x00007fff8dc11354 -[NSPersistentUIRestorer finishedRestoringWindowsWithZOrder:completionHandler:] (in AppKit)
27 0x00007fff8dac262c -[NSPersistentUIRestorer restoreStateFromRecords:usingDelegate:completionHandler:] (in AppKit)
28 0x00007fff8dac1c91 -[NSPersistentUIManager restoreAllPersistentStateRegisteringAsReadyWhenDone:completionHandler:] (in AppKit)
29 0x00007fff8dac0f37 -[NSApplication _reopenWindowsAsNecessaryIncludingRestorableState:registeringAsReady:completionHandler:] (in AppKit)
30 0x00007fff8dac0c69 -[NSApplication(NSAppleEventHandling) _handleAEOpenEvent:] (in AppKit)
31 0x00007fff8dac06b5 -[NSApplication(NSAppleEventHandling) _handleCoreEvent:withReplyEvent:] (in AppKit)
32 0x00007fff8621a458 -[NSAppleEventManager dispatchRawAppleEvent:withRawReply:handlerRefCon:] (in Foundation)
33 0x00007fff8621a2c9 _NSAppleEventManagerGenericHandler (in Foundation)
34 0x00007fff920d499c aeDispatchAppleEvent(AEDesc const*, AEDesc*, unsigned int, unsigned char*) (in AE)
35 0x00007fff920d4719 dispatchEventAndSendReply(AEDesc const*, AEDesc*) (in AE)
36 0x00007fff920d4623 aeProcessAppleEvent (in AE)
37 0x00007fff8fcdb37e AEProcessAppleEvent (in HIToolbox)
38 0x00007fff8dabcd76 _DPSNextEvent (in AppKit)
39 0x00007fff8dabbe80 -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] (in AppKit)
40 0x00007fff8daafe23 -[NSApplication run] (in AppKit)
41 0x00007fff8da9b2d4 NSApplicationMain (in AppKit)
42 0x0000000109bead17 (in Xcode)
43 0x0000000109beaca8 (in Xcode)

Answer 1

It looks like since 10.10 there is no way to allow work xcode 4.5 and xcode 4.4 (although OSX 10.9 allows workaround for this)
So you should use OSX 10.9 (Mavericks) if you want to start them.
And... Why you want to use Xcode 4.5? I don't know any reason to use it.
Xcode 4.4.1 - last version which allows to debug on armv6 device.
Xcode 4.6.3 - contains last SDK before iOS 7 design (SDK 6.1).
But what is the reason for Xcode 4.5.2?