Four steps · Stage 1
Install Z0
Z0 prepares Tekkit 2 for this Mac and hands play back to official Technic.
Put Z0 in Applications
Download the ZIP, open it, and move Z0.app into your Applications folder. Open Z0 normally. The current release is signed and notarized by Apple.
Prepare official Technic
Install the official Technic Launcher, sign in with your genuine Minecraft account, and install Tekkit 2 1.2.6. Z0 does not install the launcher, the pack, or Minecraft.
Check the two runtimes
Technic needs arm64 Azul Zulu 8. Tekkit 2 itself uses Technic’s Intel Java 8 under Rosetta 2 because its LWJGL 2 native libraries are Intel-only.
Tune, then play in Technic
Open Z0, let it inspect the certified pack, and apply Balanced. Z0 creates a backup, then opens Technic. Select Tekkit 2 and press Play there.