For those working with Lightroom on an external display (not their "main" display - e.g. external wide gamut display connected to a laptop) an issue to be aware of:
Lightroom uses the correct display profile (the external one) when viewing images normally on the external display BUT when soft proofing is switched on Lightroom incorrectly switches to use the main display profile (NOT the correct external one) before applying the soft proof conditions, this results in an incorrect soft proof on the external display.
A work around for this is:
1. To close the lid of your laptop, therefore allocating the external display as the main display.
2. Setting the "main" display (e.g. laptop) to use the external display profile - resulting in pretty bad colour on your "main" display but correct soft proofing on your external display.
The bug has not been fixed in Lr 5.2 but was only pointed out fairly recently so I guess it'll take a bit longer to be fixed.