What third-party tools help with complex creature animations in mods?

[Nathan.P]

I'm working on a total conversion mod for a popular open-world game, and I've hit a wall with the official modding tools when it comes to creating custom animations for new creature models. The documentation is sparse, and the scripting API seems to have undocumented limitations. For other modders who have pushed the engine's limits, what third-party tools or workarounds have you found most effective for complex animation rigging and importing custom assets? How do you approach reverse-engineering file formats or creating your own plugins when the official kit falls short, and are there any specific communities or resources you'd recommend for troubleshooting deep technical issues like memory allocation or shader conflicts?