For anyone who needs a little help learning how to modify the ship specs for SFC3, the SFCX site is now hosting "Engineering 402: Starship Design and Production" by yours truly. The tutorial is in PDF format, and zipped for easy download.
The tutorial runs through the basics of modifying existing ships and creating new ones. It teaches the basics by walking you through each step. The latter half of the tutorial helps you create a cloaking USS Defiant for single-player use.
Remember, if you edit any of the game files, including these ship specs, you may have problems playing the game in multiplayer modes. Please save backups of the original files, and be aware that you will need to swap your modified files and the default ones whenever going back and forth between mod play and multiplayer.
The same techniques will work for anyone hosting a server who wants to use a custom set of ship specs. However, if you modify the DefaultCore.txt, players who want to join your campaign will have to download the file.
Get the Engineering 402 tutorial from SFCX.Included in the zip download are the two finished spec files you should end up with after completing the latter part of the tutorial. Feel free to compare your files with these if you get stuck.
If anyone needs to review the old Taldren forum topic replies,
here's the thread.