Has the Process Version changed in LR 5.5?

Question

I have downloaded LR5.5 and have gone through a final selection of images for printing; most of these I had modified using LR 5.4.
With 5.5 a fair number of the images showed a considerable degree of highlight clipping which was not apparent when processed on 5.4.
Other problems include slow start up vs 5.4 and the before/after view is now very very slow. I have not altered any computer settings.
I downloaded LR 5.5 from the Adobe LR website and have also downloaded Photoshop 2014 from Creative Cloud as a trial; can this have altered the response times and image processing?
Lightroom version: 5.5 [968504]
Operating system: Windows 7 Home Premium Edition
Version: 6.1 [7601]
Application architecture: x64
System architecture: x64
Logical processor count: 4
Processor speed: 3.3 GHz
Built-in memory: 16360.9 MB
Real memory available to Lightroom: 16360.9 MB
Real memory used by Lightroom: 1013.0 MB (6.1%)
Virtual memory used by Lightroom: 1009.4 MB
Memory cache size: 71.5 MB
Maximum thread count used by Camera Raw: 4
System DPI setting: 125 DPI
Desktop composition enabled: Yes
Displays: 1) 2560x1440, 2) 1600x1200
Application folder: C:\Program Files\Adobe\Adobe Photoshop Lightroom 5.5
Library Path: E:\Lightroom Catelogues\LR_5 Catalog\Photo_R-2-2.lrcat
Settings Folder: C:\Users\Allan\AppData\Roaming\Adobe\Lightroom
Installed Plugins:
1) Behance
2) Canon Tether Plugin
3) Facebook
4) Flickr
5) HDR Efex Pro 2
6) Leica Tether Plugin
7) Nikon Tether Plugin
Config.lua flags: None
Adapter #1: Vendor : 10de
    Device : 1245
    Subsystem : 13513842
    Revision : a1
    Video Memory : 977
AudioDeviceIOBlockSize: 1024
AudioDeviceName: Speakers (Realtek High Definition Audio)
AudioDeviceNumberOfChannels: 2
AudioDeviceSampleRate: 44100
Build: Uninitialized
CardID: 4677
Direct2DEnabled: false
GPUDevice: D3D
MaxTexture2DSize: 8192
OGLEnabled: true
Renderer: NVIDIA GeForce GTS 450  
ShaderModel: 11.1
Vendor: Nvidia
VendorID: 4318
Version: 10de:1245:13513842:00a1

Answer 1

Allan Devon wrote:
Thanks for all the replies, I guess it is one of those quirks. I uploaded some of the images into Photoshop and the same clipping appeared in Camera Raw, thus it probably not LR Preference file corruption so I guess I didn't do the job right first time round!
Perhaps you adjusted those images with a different rendering intent, or they simply have blown highlights that aren't really recoverable. When I see something like this in LR it was usually done on purpose, but for a forgotten reason......