Here is some notes from last month's Boston Voice Users meeting about using DNS with Linux. The notes are on the form of Q&A, with many of the questions originating in replies to the original meeting announcement thread,
Boston Voice users December 11 meeting announcement .

I've started a new thread both because the title of the old thread is somewhat obscure and to put the thread into the Linux forum. The comments are a mixture of mine and Susan Cragin's.

Don Nicklas
Boston Voice Users
http://www.bostonvoiceusers.org/

0.) What's the best thing about using DNS9 on Linux?

Right now, continuous text entry into Notepad is a joy... works
at least as well as it does under Windows, in terms of accuracy and
speed.
The worst thing is that many of the commands do not work.
The annoying thing is that the user has to accept most of the
default options.
The most frustrating thing is that the command "open dictation
box" does not work, since dictating into dictation box yields superb
results.

1.) I wonder how the Professional version would work with Linux?

It doesn't. Almost all of the development effort is being put into
making Standard and Preferred work.

2.) Is there a downloadable document somewhere detailing how to get
DNS and Linux working?

http://ossri.harvee.org/NaturallySpeakingWine

3.a) Is Ubuntu the preferred version of Linux for this?

YES.

3.b) Will other Linux variations (Gentoo/Redhat/etc) work?

YES.
Ubuntu has been tested and is preferred. Studio has a low-latency
kernel that may give better results, but all versions work very well.
Mandriva and Red Hat -- we have been informed by people in Australia that
these have been gotten to work, at least with version 7.3.

4.) What version of Wine is required?

Use the latest available. This is always good practice.

5.) How difficult is the installation of Wine and DNS?

As demonstrated during the meeting, it did not seem very difficult.

6.) What sound system do they use for the Linux... is there a tutorial
for putting it on?

“ALSA,” which comes standard with Linux, so no tutorial required.

7.) What sound architecture under Linux is appropriate or required.

“ALSA” -- and you have to use ALSA to set the sound level before
running DNS.

8.) What version numbers of DNS have been tried with Wine?

7.3, 8.1, 9.0, 9.5, Standard and Preferred.

9.) Which type has worked/been tested: Standard, Preferred or
Professional?

Most of the Wine effort has been focused on Standard and Preferred.
These versions work: DNS Standard v7.3 and 8.1; DNS Preferred v7.3,
8.1 and 9.0 work under Wine. Standard 9.5 and the Preferred upgrade to
9.5 install but do not work because of some fairly simple errors in
oleacc.dll that are being worked on.

10.) What about extensions such as Vocola, Unimacro and
Natlink/Natpython?

I do not know if these have been tested under Wine. So far among the
WINE people involved in the development, there has been little interest.
If anyone wishes to try particularly Natlink/NatPython they should
e-mail me personally, susa...@earthlink.net ,
with a copy to whatever list if they want the thread to be public.

11.) What limitations have you found in using DNS on Linux?

General speech recognition works for text entry into Wine programs.
The Accuracy Center does not. "Notepad" works (although, oddly enough,
changing fonts can cause freezes).
"DragonPad" works well, slower than Notepad, but some of its custom
features work. "Correct [text]" works.
Not all commands work ("All Caps", for example fails; but "Insert
Before" works.) The dictation box works well but must be started with the
mouse, the voice command "open dictation box" does not work.
Training works, but not all the graphics on the training forms work as
expected. Train with John Kennedy's speech for best results.

Wine is now in beta. The comment at the meeting was at that Wine is at
the stage now of adding in all the appropriate Windows bugs; making
Wine bug for bug compatible with Windows. This is a cheeky way of saying
some Windows DLLs have bugs that will not be fixed and software
vendors such as ScanSoft have to work with. People writing Windows emulators
such as Wine not only have to write their DLLs to work as they are
supposed to, but they also have to replicate the bugs
that are expected to be there and are actually used by application
programs.

12.) How stable is DNS in Linux?

Stable once you figure out the quirks. For instance, DNS seems to loose
focus every once in a while, but focus can be re-captured by turning
the microphone off and on.

13.) Does "Select and Say" work at all?

Yes. It works well and quickly.