As a general rule, if a mod has two versions (say, MasterController, which currently has version 134 and version 135), you want the most up-to-date version (and only that version).
For mods like ErrorTrap, which has version 100, plus Patch 1.67, pick the one corresponding to how you play TS3. If from disk pick the CD download icon, from Steam pick the Steam logo, otherwise, version 100. Since its a core mod, you should be aware reasonably quickly if you got the wrong download. :-)