Planet Zoo originally shipped with Denuvo anti-tamper (which slows performance and requires online activation). By the time v1.2.5 was released, the protection was cracked. xatab’s repack includes a stable emulator (usually based on Steam Emu or Codex) that allows offline play without the launcher.
If you're having a specific technical issue with that repack (crashes, missing DLCs, errors with build number “63260”), that's likely because repacks often have modified files, missing updates, or conflicts with antivirus software. Planet Zoo -1 2 5 63260 4 DLC- RePack from xatab