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Neshke's Extendable Spawning System (NESS)

This spawning system allows experienced developers to tailor their creature spawns to their tastes, while also being easy enough to use for beginner designers to include in their modules and get up and running quickly.

There is an excellent tutorial on using NESS (created and maintained by Mark Morris [aka Black Cloud]), here.

NESS Downloads     NEW! (7/06/04) NESS_8_1_3Full.rar Full NESS 8.1.3 (59K)
  NEW! (7/06/04) NESS_8_1_3Upd.rar NESS 8.1.2 to NESS 8.1.3 Update (36K)Thanks to Cereborn for providing these updates!   (5/20/04) NESS_8_1_2Full.rar Full NESS 8.1.2 (59K)
  (5/20/04) NESS_8_1_2Upd.rar NESS 8.1.1 to NESS 8.1.2 Update (41K)  (5/19/04) NESS_8_1_1Full.rar Full NESS 8.1.1 (59K)  (5/19/04) NESS_8_1_1Upd.rar NESS 8.1 to NESS 8.1.1 Update (41K)  NESS8_1Full.rar Full NESS 8.1 (59K)  NESS8_1Upd.rar NESS 8.0 to NESS 8.1 Update (42K)  NESS8_0Full.rar NESS 8.0 (56K)  ANESS122toNESS80.rar ALFA NESS ver 1.2.2 to NESS 8.0 Update (43K)  ANESS1_2_2Full.zip Full ANESS 1.2.2 (57K)  ANESS703to122Upd.zip Team ALFA enhanced NESS 7.03 to ANESS 1.2.2 update (47K)  NESS_703Full.zip Full Team ALFA enhanced NESS 7.03 (76K)  NESS_703Update.zip NESS 7.00 to Team ALFA enhanced NESS 7.03 update (31K)  spawn_v70.zip NESS 7.00 (51K)

Other Downloads     Spawn Waypoint Generator (SWG) SWG is an utility used to ease the task of generating the waypoint names used by the spawn system to create the encounters.  hc_corpse_files.zip
(only needed by ANESS) This file containes the four missing resource file files from ANESS. These files come from the HCR and are used to replace the default chest sound when searching lootable corpses.

Forums

Latest NESS thread on the Bioware® Forums (must be member)

You can find previous threads on NESS, which contain very useful information:
here
here
here
here
here
here
here
here
here
here
here
here
and here

Keep in mind that some of these may have been archived for the really far back ones...