Companion 8.5 includes a feature sometimes called "anti-no-script," which allows the controller's operating system to continue functioning after teleporting into script-disabled parcels. We decided this was necessary for customer experience, as parcels with scripts disabled can impair vital functionality like speaking and teleporting because of interactions with RLV.
Unfortunately, nothing is ever completely painless on the grid, and our method for doing this has some side-effects. The feature is implemented by capturing control input, much like a vehicle or weapon, and occasionally products of these types can be impacted. More noticeably, however, Second Life does not play turning animations when inputs are grabbed in this way, and the avatar will not turn around when backing up. This is presumably desirable for a vehicle driver, but can diminish the experience of animation overriders.
We do have a partial workaround, however. Modern versions (8.5.7 and newer) of the Chassis Specification Unit, an add-on available from our main store in-world for L$ 300, includes an animation overrider that correctly handles turning animations, by playing them when the avatar is standing and its turning keys are pressed. This does not solve camera problems with reversing or issues with vehicle/weapon inputs, but it does resolve the most frequently-encountered and obvious consequence of the anti-no-script system. (As far as we know, this problem can't be solved without modifying your animation overrider.)
The CSU can also provide robotic movement sound effects, settings tweaks, and more. It has been a consistently popular accessory since it was released, and has a low footprint—three scripts across two prims, which can be moved into another attachment to save further on resources. AO functionality works with most popular notecard formats (Vista/Akeyo, Zhao II, and Oracul) and can be enabled, switched, or disabled through controller system commands, making it easy to integrate AO changes into system scripts.