+1 for the Taco RC filters. I bought the multi-coated four pack that includes a case and lens cap/gimbal support. They're a big improvement over the cheaper inserts and seem to be at least as nice as the more expensive ones from other vendors.
Yep. Lost mine when I tried to slide the controller into the DJI hard shell backpack once without noticing that the charging cap was still protruding slightly. Solid design there...
It depends on when you go. It's a big enough park that there are usually empty areas almost any time though. Daytime during the week is great if you can swing it.
Unless they changed it very recently, the maximum is eight seconds. Even as stable as the P3 can be, getting a usable photo at eight seconds takes perfect conditions and a bit of luck. Getting quality results at 30 would be out of the question.
I'm a little late to this thread, but there's nothing shady about using a domain privacy service. Aside from sharing your physical location with anyone who wants to cause you trouble, you get absolutely inundated with automated physical junk mail if you publish your address.
Also, this is the...
Are you waiting a minute or two? It doesn't start updating right away. I believe it mentions 60 seconds in the manual. It's painfully long delay, where you have no feedback.
What has always worked for me is to format a USB memory stick, put the firmware on that completely empty drive, and then update the controller from that. Whenever I've omitted the formatting step, I've had results similar to what you're describing.