YES! In the Development section over at Descentforum.net you can get the latest version of D3 Edit and other more D3 Editing tools.

Currently not. Though rumours have been confirmed that such a converter exists, the author almost definitely does not plan to release it to prevent tons of unapproved ports of original D1/D2 levels.

A possible way to port a certain level (after having received the author's permission, certainly) is to get the Descent Manager tool 'Levelview' from http://www.descent-network.com/descman/ and convert the level to the dxf-format. After that you can convert it to the Outrage room format with dxf2orf.

Now you've got the whole level as a room file that can be imported into D3 Edit. However, you got to flip most of the normals manually as well as retexture the whole level plus add all the scripting and stuff which is quite a lot of work...

Well, currently some MOD's are already available (see section [9.7]) and others in are the works. Possibly the best place to start for you if you wanna work on MODs yourself is the D3sdk Webpage @ http://d3sdk.warpcore.org/. As they say:

"This should be one of the most extensive resources for making D3 Mods on the web. We have several great minds at work to help everyone get the creative juices flowing. Hopefully we can help you unlock and create the most mind blowing mods to ever hit the multiplayer scene. The Sky is the Limit and we're here to help you get there."

Another fairly good resource is http://www.xtremebuilder.com/ with lots of tutorials and professional stuff as well. Go and see for yourself!

Please see section [9.7].

I always thought it was annoying to have the display settings overlap the rear view and cam view window so I took some hours of experimenting. Well, here's how to do it: in this example I will change both the name *and* position of the Shields, Energy and Afterburner display on the Pyro's HUD; once you get the hang of it you can modify other gauges/ships/languages accordingly.

• extract 'D3.str' and 'hud.inf' from the D3 HOG
• open 'D3.str' in any text editor and jump to the line which describes the settings to be modified, in my case:

  !/!550: Shields display on the hud
  !/!551: Hud display for energy
  !/!552: Hud display for afterburner
  

• the lines below these 'headlines' determine the name of the setting on your HUD
• change

  'Shields' to 'S'
  'Energy' to 'E'
  'Afterburner' to 'A'

• save the file and copy it to the D3 root directory, e.g. e:\games\D3\d3.str
  
• open 'hud.inf' in any text editor and jump to

  @ shields
  type=3
  rgb=96,96,240
  pos=262,320
  textpos=1,440
  create
  

• 'textpos' denotes the coordinates of the shields display on your HUD set to a default resolution of 640x480. On other resolutions the coordinates will automatically be adjusted by a certain percentage so you'll get similar results. To find your preferred position for a setting you should take a screenshot at 640x480 and set the new coordinates on it.
• modify the textpos coordinates of Shields, Energy and Afterburner as you like, save the file to the D3 root directory and start D3

To give you a first impression on how it's gonna look like, check out my heavily modified Pyro HUD (71 KB) and/or download it (51 KB). Simply unzip the files to your D3 main directory and start a game with the Pyro.

I'm quite sure you'll find some interesting stuff in these text files so have fun exploring. Note that these settings only apply to your system, e.g. if you change some statistical messages like 'Moon experiences technical difficulties' to 'Well Moon, doesn't that just take the biscuit?' the other players won't see the latter.