Hi,
Currently, our plug-ins do not yet support the latest Arnold updates. We plan to release an update for compatibility with Arnold 7.3 and 3ds Max 2025 soon, but we haven't set a release date yet. Typically, we release versions of our plugins (Forest Pack & RailClone) shortly after the corresponding 3ds Max support (in this case, 3ds Max 2025) becomes available. However, we still have several adjustments to make in the upcoming versions, so the release might be delayed. Thank you for your patience.
In the meantime, we recommend using MAXtoA 5.6.6.4. To downgrade to this version, please uninstall the current version via Apps & Features.
Best regards,