Text := "<1><2><3><4>"

Rep := RegExReplace(Text, "<(\d+)>", "$1|")	; Извлекаем числа.
Sort, Rep, R N D|			; Сортировка реверсная, числовая, '|' как делитель.
Rep := RTrim(Rep, "|")		; Убрать последний символ '|'.
MsgBox, % Rep				; Отображаем строку.

;Превращаем строку в список:
Arr := StrSplit(Rep, "|")
For k,v in Arr
 MsgBox, % "Индекс:`t`t" k "`nСодержимое:`t" v

n := "<1><2><3><4>"

arr := StrSplit(n, "<", ">")
max := arr.MaxIndex()
Loop % max
   MsgBox, % RegExReplace( arr[ max - A_Index + 1 ], "<(\d+)>", "$1" )

cmt_pages=
(
"id": "1",
"id": "2",
"id": "3",
"id": "4",
"id": "5",
"id": "6",
)
arr := StrSplit(cmt_pages, "`n", "`r")
max := arr.MaxIndex()
Loop % max
   MsgBox, % RegExReplace( arr[ max - A_Index + 1 ], """id"":\s""([^""]+).*", "$1" )

cmt_pages=
(
<1><2><3><4>
)
arr := StrSplit(cmt_pages, "`n", "`r")
max := arr.MaxIndex()
Loop % max
   MsgBox, % RegExReplace( arr[ max - A_Index + 1 ], "<(\d+)>", "$1" )

n := "<1><2><3><4>"

match := "", match1 := "", Pos := 0
While Pos := RegExMatch(n, "<(\d+)>", match, Pos + 1)
   MsgBox, %match1%