Sorry, but you didn't get the point: There's a problem with this [nice] snippet - it is the thing to fix, and that's what he is asking for.

The snippet writes a short VBscript to a custom window, safebufs and runs this script via com call: it's using an ADO-"stream" to download binary data (creating an (empty) file, buffering the data in memory, dumping the downloaded data into the file).
This procedure seem to fail if the output filepath contains spaces (?) - and it's not unlikely for $mircdir to be a filepath with spaces.

As $mircdir points to a directory where read/write access may be taken for granted, and because it's a directory often used by mIRC scripts as point of reference for data storage (e.g. at subdirectories of $mircdir), neither a hardcoded, nonspaced directory will make up a true workaround, nor will changing the mircdir itself do - you cannot demand this of "end users" - and $nofile($mircexe) *may* contain spaces as well.