The typical point spread uses (+20/+10/-10/-20)
There is no "typical" uma.
EMA: +30/+10/-10/-30 (was +9/+3/-3/-9 until 2012)
JPML A: see below
JPML B: +15/+5/-5/-15 (was +30/+10/-10/-30)
Nihon Pro Mahjong: +30/10/-10/-30 (plus oka=20, the other rules I've listed here have a 0 oka)
Saikouisen Classic: +12/+4/-4/-12
Real Mahjong Unit: +15/+5/-5/-15
Korean Mahjong League: +20/+10/-10/-20
Club Riichi de Montréal: 0/0/0/0
JPML A's uma depends on how many players are "positive" (>=30k) or "negative" (<30k):
1 player positive: +12/-1/-3/-8
2 players positive: +8/+4/-4/-8
3 players positive: +8/+3/+1/-12
all players negative: +8/+4/-4/-8
6. Round to the nearest integer. If the division result produces a digit of 0.5, then the number is rounded down.
I don't think the rounding method is consistent from one place to another.
Also, I'm pretty sure some organizations don't round at all.
I think your tables are confusing ; they mix computation results with new data without a clear distinction of which is what.
At least JPML, EMA and WRR don't use this method, but split the uma equally.
E.g. with a uma of +15/+5/-5/-15, tying for 1st and 2nd will give a +10/+10/-5/-15 uma.