About:
I wrote this to make downloading files easier on myself and thought I'd share it.

To Load:
Copy into a fresh mIRC remotes file

To Use:
/download [callback alias] [url] [path\file]

[callback alias] - The alias to be called when the file is finished downloading.
if it has multiple parameters surround it in double quotes: "echo -a"
The callback alias gets called with:
[0|1] [MSG] [URL] [FILEPATH]
Where:
[0|1] - 1 if success, 0 if download failed
[MSG] - "S_OK" if successful, or the error message of why the download failed
[URL] - The url that was to be downloaded
[FILEPATH] - the file the data was to be wrote to

[url] - The page/file you wish to download

[path\file] - The file you wish to save to, if no path is specified, $mircdir will be used.
If the filepath contains spaces, place it in double quotes: "c:\some dir\file.txt"


Example:
/download "echo -a" https://www.google.com/search?q=test example.txt alias Download {
if ($regex(Args,$1-,^-c (?|(?:"(?=.+")([^"]+)")|(\S+)) (\S+) (?|(?:"(?=.+")([^"]+)")|(\S+)) (\S+)$)) {
var %callback = $regml(Args,1)
var %url = $regml(Args,2)
var %file = $qt($regml(Args,3))
var %com = $regml(Args,4)
var %r = $iif($comerr,1,$com(%com).result)

.remove $qt($scriptdir $+ %com)
if ($com(%com)) { .comclose %com }

if (%r == -1) { %callback 1 S_OK %url $qt(%file) }
elseif (%r == 1) { %callback 0 UnKnown_ComErr %url $qt(%file) }
elseif (%r == 2) { %callback 0 IE6+_Needed %url $qt(%file) }
elseif (%r == 3) { %callback 0 Connect_Error %url $qt(%file) }
elseif (%r == 4) { %callback 0 Newer_ActiveX_Needed %url $qt(%file) }
elseif (%r == 5) { %callback 0 Writefile_Error %url $qt(%file) }
else { %callback 0 Unknown_Error %url $qt(%file) }
}
elseif ($1 != -c) {
if ($isid) || (!$regex(Args,$1-,^(?|(?:"(?=.+")([^"]+)")|(\S+)) (\S+) (?|(?:"(?=.+")([^"]+)")|(\S+))$)) || ($regml(Args,0) != 3) { return }

var %callback = $regml(Args,1)
var %url = $qt($regml(Args,2))
var %file = $qt($iif(: isin $regml(Args,3),$v2,$mircdir $+ $v2))
var %com = download $+ $ticks $+ .vbs
var %s = $qt($scriptdir $+ %com)
var %w = write %s

%w on error resume next
%w Set C = CreateObject("msxml2.xmlhttp.3.0")
%w if (err.number <> 0) then
%w err.clear
%w set C = CreateObject("msxml2.xmlhttp")
%w if (err.number <> 0) then
%w err.clear
%w set C = CreateObject("XMLHttpRequest")
%w if (err.number <> 0) then wscript.quit(2)
%w end if
%w end if
%w C.open "GET", %url $+ , false
%w C.send
%w if (err.number <> 0) then wscript.quit(3)
%w set O = createobject("adodb.stream")
%w if (err.number <> 0) then wscript.quit(4)
%w O.type=1
%w O.mode=3
%w O.open
%w O.write C.responsebody
%w O.savetofile %file $+ ,2
%w if (err.number <> 0) then wscript.quit(5)
%w O.close
%w wscript.quit(-1)

.comopen %com WScript.Shell
if ($comerr || !$comcall(%com,download -c $qt(%callback) $noqt(%url) %file,run,1,bstr*,%s,uint,1,bool,true)) { goto error }
return
}
:error
if ($error) { reseterror }
if ($isfile(%s)) { .remove %s }
if ($com(%com)) { .comclose %com }
}