Sorry there couldn't be more here to contribute to your thread. Especially ones with pictures.
As for panda I just take the entire roll and spread it out as best I can then begin stapling at one corner across the top about 1-2 feet then I go down at the corner where I started, and then top to bottom on those 1-2 feet, then continue at top and go another 1-2 feet or do it by your sections whatever is easiest for you. First time I would go slow. Just visually make it even at the top and you should hit all the corners good.
As for door leave that alone until last. I do walls, roof, floor then door. Now I'm not sure how you are doing the door, here is how I do it.
Here is my smaller flower room. It's tight in this room as there are three rooms. But this is the front door from the left side. Notice the random pieces of velcro placed on outside of door, these are for allowing me to keep my door open at different levels and for bringing over the strips of panda on each side of door after door is fully closed, the strips on the side cover where the velcro on the door frame and panda is, ensuring no light gets in or out. And you can see the frame of door is the 2x2.
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Here is door open 1/4. Notice how velcro is on frame and on white(inside) of panda.
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Here is door open a little over halfway.
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Door open about 80%(max) as rest of panda for door is stapled and gorilla taped on.
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Now looks are deceiving, this is a 7x5x7 1/2 high room, I just couldn't get a better angle and give a good door shot being another room's door is just a few foot across from this one.
You can see yoyo hangers in this room, only reason they are still there is because the room is so tall. All my other rooms have the cord set-up.
Here is this room's carbon and fan setup just above door, secured to 2x4s with heavy duty rope/racket system. Fan is screwed into 2x4 but there is rubber piece in between fan mount and wood as to lesson vibrations and noise.
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Notice how I even panda my 2x4s and 2x2s, I'm anal. And I panda from inside, door is secured on outside and to ensure no light leaks I also buy the cheaper 3-4mm thick black poly and secure that all the way around room except at door, so basically I have a layer of 6mm panda on inside of frame and 3-4mm thick poly outside.