Open source Seamless3d 2.154 modeller and server can be downloaded from:
http://seamless3d.com/download
Shared TouchSensor Events
All TouchSensor's that have a name will be automatically shared in seamless chat. Since 90% of the time when a blaxxun world builder would want shared events all they really needed them for was for TouchSensors and the only way to do this was to add protos and instances of the protos and extra routes to and from the server, seamless chat in comparison will greatly simplify adding simple shared events. And unlike in Blaxxun, TouchSensors contained in avatars will be shared too. The train's start/accelerate/decelerate/stop script in Techuelife Island is now shared in seamless chat.
ColorEffect Animation
Because Seamless does not yet have a MonoColorEffect node for simple color animation I have made it so that all parts that use a ColorEffect node can be set to any single color by writing a color value to the diffuse field.
Same for VRML/X3D, the diffuse field has no purpose when color per vertex is used so I thought why not make use of it this way. Directly setting the diffuse field using a text editor wont affect the color of the parts because the diffuse field only causes an internal event when it is written to after the world has loaded.
CopyPart scale, rotation & translation fields
By adding a scale, rotation, and translation field to the CopyPart node, it is now possible to add all the leaves to a tree from a single leaf using just a few lines of script and a single CopyPart node. These 3 transform fields allow the copied vertices to be transformed in isolation from the destination part without needing a Place node, another CopyPart node and 2 more Part nodes.
landOffset
I added this feature in response to Dajamma telling me she could no longer adjust her gammonbrat pink fairy avatar (which is fixed to the Blaxxun height) in Techuelife Island since I added the land gravity. The landOffset field allows you to adjust the height of an avatar that does not have the base set to zero height. Because this field is contained in the OpenNetFile control panel it will get saved when you close seamless and so this will make things easier than before because the user wont have to keep adjusting the height each time they log into a world. I considered making it so the base of an avatar is automatically adjusted the way they were in Blaxxun but I decided not to do this because this way did not seem to work well for Blaxxun. I remember my avatar's feet would typically be in the ground unless I moved. Also by being able to have control over the height of the avatar means the avatar modeller wont have to fight the automatic height adjustment (by adding a small triangle to the avatar's base) to make the avatar hover over the land.
autoOutSegmentedParts & outScriptAsRoutes combination
Although the autoOutSegmentedParts (export parts as regular VRML/X3D Shape & Transform nodes) option is not new, being able to combine both autoOutSegmentedParts & outScriptAsRoutes is new for 2.154. Perhaps this could be categorized as a bug-fix but it is a new feature implemented for the first time.
Bug-fixes
Import HAnim with No Skin
HAnim avatars that contained all of the geometry in HAnimSegment nodes and that had no skin could not be imported. This has now been fixed.
HAnimSegment scale
The geometry could get messed up when importing HAnimSegment nodes that are descendents of HAnimJoint nodes and when there was scaling. This has now been fixed.
Multi Effect transform bug
When plugging an Effect node into a Part node, the Part's geometry did not transform correctly for animation. This has now been fixed.
compile transform scale & compile transform scale rotation
The compile transform scale field could fail to work correctly depending on the combinations of rotations used for the skeleton. This has now been fixed.
The compile transform scale & compile transform scale rotation commands did not scale the translation fields. This has now been fixed.
Many thanks to Alain, fabricator and Dajamma for their feedback.

