Here's a small description of various versions of the Dink Smallwood
source code:

v1.07, official source, first free software release: FreeDink is
  currently based on it.

  http://www.codedojo.com/files/dink/dink_source.zip
  http://dl.sv.gnu.org/releases/freedink/dink107_source.zip


The Dink Project: first attempt to port FreeDink (with initial work by
  Christoph Reichenbach and Shawn Betts); FreeDink started as a
  continuation of that work, but since it was a quick port, numerous
  bugs remained. To ensure we get a port as close to the original as
  possible, FreeDink eventually restarted from the DirectX sources.

  The Dink Project itself stopped and was replaced by an "unofficial
  sequel to the Dink engine" written from scratch, called "Windemere",
  which eventually also stopped.

  http://sourceforge.net/projects/dink


Windowed Mode / 32-bit Mode: first support for 32-bit colors mode,
  which was included in v1.08. As such, it is not evolving anymore.
  
  http://www.dinknetwork.com/file/windowed_mode_32_bit_mode/
  http://files.dinknetwork.com/dwindowsrc.zip

reDink: a modified version of the engine with some fixes and new
  features. It is discontinued, but there are chances that part of it
  was included in v1.08 [TODO: study the code].

  http://www.dinknetwork.com/file/redink/
  http://files.dinknetwork.com/re-dink.zip


unDink "unDink is a complete over-haul of the Dink engine, which fixes
  a few thousand bugs and adds a few small features". It appears
  unmaintained, and there's little documentation available. Maybe
  there are interesting comments to read in the source code...

  Some vague information:
  http://www.dinknetwork.com/forum.cgi?MID=46320
  ("News Comments - New Source Project: unDink 2.67")
  http://www.dinknetwork.com/forum.cgi?MID=44966
  ("Development - New Source Project: unDink")

  http://www.dinknetwork.com/file/undink/
  http://files.dinknetwork.com/undink-2.67.zip
  
v1.08: official source with patches assembled by Dan Walma. 1.08 is
  the only version you can officially download now, so I think
  FreeDink should upgrade to it.

  Changes in the code are prefixed with //redink1. According the
  readme.txt: "The main changes for Dink Smallwood 1.08 are the
  introduction of true-color and windowed modes (courtesy of
  iNvERTIgO).  There have also been a few other changes and bug fixes,
  such as true-color fading, frame-rate limiting, more consistant
  player speed, inability to walk off edges of screenlocked screens, a
  few new DinkC commands, and more.". Check v1.08.txt for an attempt
  to sum-up changes.

  It introduces slight incompatibilities with the previous version,
  which may prevent some D-Mods from working correctly:
  http://www.dinknetwork.com/forum.cgi?MID=67349
  
  Actually I'd say this is god-sent: FreeDink was developped with a
  goal of absolute compatibility with 1.07; v1.08 instead expects
  D-Mods to be fixed if they rely on bugs. Thus, by basing FreeDink on
  1.08, there are fewer bugs that we need to maintain as features, and
  there is interest in releasing fixed versions of problematic
  D-Mods. This may make FreeDink easier to code. However, we need to
  either restart the port from 1.08 or merge the changes in the
  current FreeDink code base.

  http://www.dinknetwork.com/file/dink_smallwood_1_08_source_code/
  http://files.dinknetwork.com/dink108_source.zip

v1.08 Aural+: v1.08 using DirectX's DirectShow instead of W32API's
  mciSendString to play MIDIs; since DirectShow can play MP3, this is
  the first MP3-enabled version as well. It's not widely used as of
  now.

  http://www.dinknetwork.com/forum.cgi?MID=67386
  http://redrecondite.com/dink_aural+.zip


Novashell: Seth Robinson's new 2D game maker, released as free
  software. It has nothing to do with Dink Smallwood, but there are
  chances that people interested in going beyong Dink will switch to
  that engine. This makes improving the Dink engine less appealing, so
  maybe FreeDink should just stick to porting Dink to other platforms,
  and add no features whatsoever. Still, maybe people will prefer Dink
  (e.g. because they don't want to learn something else) and improving
  the Dink engine will still be needed.

  http://www.rtsoft.com/novashell/
