You can grab it here.
And here's the CHANGELOG since 1.6rc0:
* IMPORTANT: Added VS2013 (win32 & x64) support + precompiled binaries
* IMPORTANT: Added VS2012 (win32) support + precompiled binaries
* IMPORTANT: Removed official support for VS2008 & VS2010
* IMPORTANT: orxDISPLAY_EVENT_PAYLOAD has been refactored (field renaming)
* IMPORTANT: orxANIM_EVENT_PAYLOAD has been refactored (field renaming)
* IMPORTANT: Android builds are now using hard-float ABI and NDK r10b
* IMPORTANT: Android builds have been migrated from Eclipse to Android Studio
* IMPORTANT: Added support for Android TV
* Param config section will now be populated with parameters provided on the command line (full names only)
* Debug-only: orx will try to detect and warn about case config errors
* Optional context can now be provided when registering event handlers
* Animations (both current & target) can now be changed from within an animation event callback
* Added Joystick support to Android, conditional upon Android.UseJoystick config property
* Added Nexus player remote support to Android
* orxSTRUCTURES ordered as lists will not be ordered as FIFO anymore (use instead a cache friendly strategy)
* Added orxDISPLAY_EVENT_LOAD_BITMAP, orxTEXTURE_EVENT_LOAD and orxANIM_EVENT_UPDATE events
* Added Display.ShaderVersion config property, defaults to 120 on Windows, Linux & OSX
* Spawner can now handle random/list values for WaveSize, WaveDelay and ObjectSpeed
* Android audio thread is paused when application is sent to the background
* AnimSets can now contain up to 1024 anims (previously: 256)
* Command Object.Delete will now handle disabled objects correctly
* Updated stb_image to v2.0b
* Updated stb_image_write to v0.95
* Updated stb_vorbis to v1.04
* Misc fixes, optimizations and additions
