Question 1

The connections on the back center of the panel have a red and black pair stenciled 5v / red lead and din/ black. is this stenciling wrong?

Accepted Answer

The center connection on my panel is also marked that way.  The Din on the center connection is actually gnd or 0v.  It is connected to the gnd wires on the ends of the panel.  (you can verify this with an ohmmeter)  It is best to apply 5v and gnd to all three sets of wires to avoid voltage drops across the panel.

Question 2

What else do I need to operate this panel

Accepted Answer

Well if this is your first time to operate this LED panel , you can use the K-1000C controller , the DC5V10A power supply .  You can use the K1000C to program a scrolling test, photo , some chasing lighting effect . 
K-1000C  teaching video 
https://www.youtube.com/watch?v=sD8moscZOVU&t=20s
There are 4 parts . If you are a beginner , please watch all of them .

Part 1(start time 00:05-03:12) : This part I teach you how to connect the power supply , controller and the LED strip . It is also used to check the connection before you program a file for the project .

Part 2(start time 03:12-18:16) : I will teach you how to program a lighting effect for you WS2812B 16X16 LED matrix panel . It is the same way to program a file for other addressable panels.

Part 3(start time 18:17-25:07): I will teach you how to program a lighting effect a lighting effect for WS2812B LED strip . When you learn this , you can program a lighting effect for all the smart IC led strip .

Part 4(start time 25:08-36:05) : I will teach you how to connect two K1000C controller to control  3000 Pixels Panel . We call it Cascade synchronization

US amazon link 
K-1000C : https://www.amazon.com/dp/B06XJ1J915
DC5V10A power supply : https://www.amazon.com/dp/B01D8FM71S

Anyother question , you can contact us support@btf-lighting.com

Question 3

Do you have any versions that do not bend?

Accepted Answer

This is flexible PCB board , we can make it unbendable . It depends on how many do you want ? You can contact us   support@btf-lighting.com

Question 4

Can this be operated by battery?

Accepted Answer

this must be DC5V .
In theory is possible, if your battery is DC5V .However, it is difficult to guarantee working hours , it deepends on your battery capacity.
We recommand the power adapter DC5V10A for this product

ASIN	B01DC0IPVU
Additional Features	Chasing Color, Individually Addressable DIY, LED Matrix, Pure Gold Wire, WS2812B IC Chip
Best Sellers Rank	#10,772 in Musical Instruments ( See Top 100 in Musical Instruments ) #99 in Stage Lights
Brand Name	BTF-LIGHTING
Color	Black
Connectivity Protocol	SPI
Connectivity Technology	Custom 3-pin connector
Control Method	App
Controller Type	Button Control
Customer Reviews	4.4 4.4 out of 5 stars (467)
Form Factor	Flexible
Included Components	3 PIN male connector
Indoor Outdoor Usage	Outdoor
Item Dimensions	12.6 x 3.15 x 0.12 inches
Item Length	32 Centimeters
Item Weight	0.1 Kilograms
Light Color	RGB
Light Source Type	LED
Manufacturer	BTF-LIGHTING Technology Co., Limited
Manufacturer Part Number	WS2812B-8x32
Manufacturer Warranty Description	Indoor use only.
Material Type	Plastic
Model Number	WS2812B-8x32
Number of Items	1
Number of Light Sources	256
Occasion	Indoor
Power Source	DC
Product Style	Modern
Theme	Christmas
UPC	602938070416
Unit Count	1.05 Feet
Voltage	5 Volts
Water Resistance Level	Water Resistant
Wattage	76.00

BTF-LIGHTING WS2812B RGB 5050SMD Individually Addressable Digital 8x32 256 Pixels 12.5in x 3.1in LED Matrix Flexible FPCB Full Color Works with SP802E,etc Controllers Image Video Text Display DC5V

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