I am using FDM 3.0 build 848 on Windows Vista 32-bit SP1
I am trying to test the ability for it to resume a failed download. The HTTP response from the TiVo seems to indicate that it supports the resume, but FDM does not accept this and restarts from the beginning.

Noteworthy download settings:
- username and password required
- the TiVo does NOT support "query size" (perhaps this is the culprit) but includes a custom HTTP response header that is similar called TiVo-Estimated-Length
- I am allowing only 1 simultaneous connection to server so I've set max sections to 1
- using HTTP 1.1, cookies, and FDM's user agent
- i have disabled rollback on broken connections

The resume works fine if I use TiVo's normal download client software (TiVo Desktop) instead of FDM

Here is the log:
9:11:40 PM 3/25/2009 Starting download...
9:11:40 PM 3/25/2009 GET /download/sometvshow.TiVo?Container=%2FNowPlaying&id=4213604&Format=video/x-tivo-mpeg HTTP/1.1
Referer: http://192.168.1.102/download/
Cookie: sid=9D0E5672657EC372
Host: 192.168.1.102
9:11:43 PM 3/25/2009 HTTP/1.1 200 File Follows
Server: tivo-httpd-1:9.3.2a-01-2:240
Content-Type: video/x-tivo-mpeg
Transfer-Encoding: chunked
TiVo-Estimated-Length: 782237696
Connection: close


9:11:43 PM 3/25/2009 Opening file on the disk...
9:11:43 PM 3/25/2009 Succeeded
9:11:43 PM 3/25/2009 [Section 1] - Started
9:11:43 PM 3/25/2009 [Section 1] - Downloading

...

9:11:49 PM 3/25/2009 [Section 1] - Stopped
9:11:49 PM 3/25/2009 Stopped

...

9:11:55 PM 3/25/2009 Starting download...
9:11:55 PM 3/25/2009 GET /download/sometvshow.TiVo?Container=%2FNowPlaying&id=4213604&Format=video/x-tivo-mpeg HTTP/1.1
Referer: http://192.168.1.102/download/
Range: bytes=61296-
Cookie: sid=9D0E5672657EC372
Host: 192.168.1.102
9:11:57 PM 3/25/2009 HTTP/1.1 206 Partial File Follows
Server: tivo-httpd-1:9.3.2a-01-2:240
Content-Range: bytes 61296-
Content-Type: video/x-tivo-mpeg
Transfer-Encoding: chunked
TiVo-Estimated-Length: 782237696
Connection: close


9:11:57 PM 3/25/2009 Server doesn't support download resuming. Restart from the beginning
9:11:57 PM 3/25/2009 GET /download/sometvshow.TiVo?Container=%2FNowPlaying&id=4213604&Format=video/x-tivo-mpeg HTTP/1.1
Referer: http://192.168.1.102/download/
Cookie: sid=9D0E5672657EC372
Host: 192.168.1.102
9:12:01 PM 3/25/2009 HTTP/1.1 200 File Follows
Server: tivo-httpd-1:9.3.2a-01-2:240
Content-Type: video/x-tivo-mpeg
Transfer-Encoding: chunked
TiVo-Estimated-Length: 782237696
Connection: close


9:12:01 PM 3/25/2009 Opening file on the disk...
9:12:01 PM 3/25/2009 Succeeded
9:12:01 PM 3/25/2009 [Section 1] - Started
9:12:01 PM 3/25/2009 Server does not support download resuming. Don't stop this download; otherwise you'll have to start it from the beginning
9:12:01 PM 3/25/2009 [Section 1] - Downloading
9:12:03 PM 3/25/2009 [Section 1] - Stopped
9:12:03 PM 3/25/2009 Stopped