Honestly, i didn't try your snippet but when i was reading your code, i thought these tips might be useful for you:
1) This alias will cause an error if the dialog is already open:

alias autotalker { dialog -dm autotalker autotalker }

It's better to write like this:

alias autotalker {
  dialog $iif($dialog(autotalker),-v,-dm autotalker) autotalker
}

2) When you want to add some items in a ComboBox, you can use /didtok instead of adding your items one by one

  /did -ca add 2 None
  /did -a add 2 White
  /did -a add 2 Green
  /did -a add 2 Purple
  /did -a add 2 Red
  /did -a add 2 Cyan
  /did -a add 2 Glow1
  /did -a add 2 Glow2
  /did -a add 2 Glow3
  /did -a add 2 Flash1
  /did -a add 2 Flash2
  /did -a add 2 Flash3
  /did -ca add 3 None
  /did -a add 3 Wave
  /did -a add 3 Wave2
  /did -a add 3 Slide
  /did -a add 3 Shake
  /did -a add 3 Scroll

Could be:

didtok $dname 2 32 None White Green Purple Red Cyan Glow1 Glow2 Glow3 Flash1 Flash2 Flash3
did -c $dname 2 1
didtok $dname 3 32 None Wave Wave2 Slide Shake Scroll
did -c $dname 3 1

3) And all off those slashes are useless in remote.
4) When you're writing an addon or a snippet, you MUST use $scriptdir to save your data, but you're using mIRC's root directory.

while ($did(1,%x)) {
  write AutoTalker\AutoText.txt $v1
  inc %x
}

This can be done by adding a $scriptdir in your code like this:

while ($did(1,%x)) {
  write $scriptdirAutoText.txt $v1
  inc %x
}

Hope i could help you a bit to improve your snippet.
Good Luck.