Another Strange Crossword

Question

Solve the strangely-shaped crossword.

Then find the answer word describing how PSE treats new users.

_{Sorry- no text version of the crossword image. It is difficult for me to fit all that info into text. Maybe someone else better than me can work some magic.}

Across
1 R. Kelly believes he can.
2 Beware of taking this from mainstream media; advice
3 Thankfully, "soothing syrup" use hit this over 100 years ago.
6 When sharing, a single is OK, but a double is bad.
9 Used to drown out wife's "fix-it" requests
10 All things do this. Only kids love it. (British)
11 Would be strange if things fell this way
12 Cats carry kittens by this. Ouch!
14 Who said "Do these genes make me look fat?"
15 Bill Clinton can articulate this definition.
16 Pickles are ____icious.
17 Time required for wife to get ready
19 A few glasses of this gives you more important things to say.
20 P. Diddy's reaction to clowns
22 Evel Knievel was a regular here.
24 How I sleep when losing my religion
25 Necessary to "make it rain"
27 Possible consideration when on a cruise with mother-in-law
29 Used before an author's name
30 Well, it never bothered Elsa.
33 Let's hope their strange magic won't bring me down.
34 The first part of every ah-ha moment
36 Measure for ice cream when sad or depressed
37 Popular highball for a jolt and a buzz (abbrev.)
38 Enforces laws; often ignorant of his authority's limits. (abbrev)
39 It was water before it was cool.
40 When lost, many men resist this solution.

Down
3 Refuses to mate, even to avoid extinction
4 Lightning-fast version of snail mail
5 Top tech brand for high quality and ridiculous prices
6 Chronic teller of corny jokes
7 Strategy for conquering trolls
8 Princess's sensitivity-testing legume
11 Genus of a lichen likened to an old man's beard
13 Spanish masc. definite article
15 Peak: "King of Gods" lover; Low Point: Became a tormented heifer
17 Duration of humanity's love for pizza
18 These citizens get the best discounts.
20 Judge Doom to Roger
21 Skill type tested when wife finds unknown lipstick in your car
23 The face your co-worker hopes to show "that new chick from logistics"
25 In China, between a monkey and a dog
26 You can lean on me when looking out your window.
28 Wear me, or add "um" and listen to me.
31 Jed called it Texas Tea.
32 Tough word for some fiancés to say
35 My reply when strangers say of my toddler son: "She's precious!"

Answer 1

To new users, PSE is:

WELCOMING.

The solutions:

Across: 1 fly 2 tip 3 peak 6 dip 9 amp 10 ageing 11 up 12 nape 14 dna 15 is 16 dill 17 eons 19 ale 20 fright 22 er 24 rem 25 cash 27 maroon 29 by 30 cold 33 elo 34 ah 36 kilo 37 rbv 38 leo 39 ice 40 ask

Down: 3 panda 4 e-mail 5 apple 6 dad 7 ignore 8 pea 11 usnea 13 el 15 io 17 eternal 18 sr 20 framer 21 improv 23 oh 25 cock 26 sill 28 alb 31 oil 32 do 35 he

(Sorry for the rather plain presentation.)

The highlighted cells:

They grey cells spell FLIP DIMENSIONS FOR EACH PRIMARY COLOR BLOCK.

The crossword puzzle is a 15×15 grid, subdivided into three 5×15 columns, each marked with one of the primary colours. To "flip dimensions" means to re-arrange each 5×15 block into a 15×5 block so that the black and white cells are the same when "read" row-wise. (You can imagine this as word-wrapping a text to three times its width, if you like.)

If we do that and space out each 5×5 sub-block, we get:

   red                 yellow              blue

   #...# ##### #....   ##### ##### #...#   ##### #...# #####
   #...# #.... #....   #.... #...# ##.##   ..#.. ##..# #....
   #...# ####. #....   #.... #...# #.#.#   ..#.. #.#.# #.###
   #.#.# #.... #....   #.... #...# #...#   ..#.. #..## #...#
   ##.## ##### #####   ##### ##### #...#   ##### #...# #####