There is currently no user interface for this in the Save Meshes script, but I have written some internal tools to do just that. So here is a workaround until we add this as a feature of a future XMesh build:
As I have mentioned more than once, XMesh Saver is a kind of a renderer. It respects the Renderable property of scene objects, and also happens to respect the renderable property of TP Groups! In other words, if you uncheck all renderable flags of all groups except for one, saving the TP will save just that one group!
Krakatoa provides a UI for this under the Krakatoa Explorers (you have to add Krakatoa as the current renderer to enable the Explorers). The “Thinking Particles Groups” rollout of the Krakatoa Explorers shows all Groups of all scene TP systems in two lists - left list is Non-Renderable, right one is Renderable, Just move all groups except for the ones you want to save to XMesh to the left list. Save XMesh. Change the Groups and the output path and save again and so on. This way, you can produce multiple XMeshes from various TP groups, or just one XMesh from the groups you actually want to render (assuming other groups contain data you don’t want to save).
thinkboxsoftware.com/krak-th … rt-groups/
Hope this helps.