Hello,
I've prepared an Experimental YafaRay version (I called it v0.1.99-beta1) with several changes respect to the current official YafaRay v0.1.5:
* Works with Blender 2.74 (official Windows 64 download from Blender) in Windows 7 64bit and Windows 8.1 64bits
* Fixes for Volumetrics (already merged in YafaRay source code). See:
http://www.yafaray.org/community/forum/viewtopic.php?f=22&t=5036&start=15* povmaniaco fix for Volumetrics when using SPPM (already merged in YafaRay source code). See:
https://github.com/YafaRay/Core/commit/6f0fdafa4daf2469a020864ce3e7015459513314* New Clay Material render system, more powerful (not yet merged in YafaRay source code). See:
http://www.yafaray.org/community/forum/viewtopic.php?f=16&t=5079* New Texture Mapping for Sigma factor of Oren-Nayar shader in Shiny Diffuse material (not yet merged in YafaRay source code). See:
http://www.yafaray.org/community/forum/viewtopic.php?p=31037#p31037* Fix for Inverted color when mapping Voronoi/Musgrave to diffuse color (not yet merged in YafaRay source code). See:
http://www.yafaray.org/node/187* Fix for Exception in yafaray-xml when using xstart/ystart different than zero. See:
http://www.yafaray.org/node/597 The Windows 64bit build can be downloaded from:
https://github.com/DavidBluecame/Blender-Exporter/releases/download/v0.1.99-beta1/YafaRay.v0.1.99-beta1.2015-04-11.-.experimental.build.for.Blender.2.74.Windows.7-8.1.64bit.zipPlease test it and let us know if it works for you or if you have any new issues or problems. If all works fine, perhaps these improvements will be included in the next official version of YafaRay.
I hope it helps! Best regards. David.