Nice to see that you are working on it.  :)

Several comments:
- Be careful when writing @TRs, the space after # is problematic. Please, check all of them.
"helptext|HelpText Download From URL# Just enter the URL(s) to download from"

- Why do not you use the webif^2 helplink?

"helptext|HelpText Additional options#See curl manual. (optional)
helplink|http://curl.haxx.se/docs/manual.html"

- Watch unwanted spaces. If you really need it, use  . This is one of the webif-page's quirks, it strips whitespaces.

"submit|download_url|Download From URL |"
should be
"submit|download_url|@TR<<Download From URL>>|"
or if you want spaces
submit|download_url|@TR<<&nbsp;Download From URL&nbsp;>>|

- I have wondered what the RIST term was.  :)

I am checking the queue idea....