Curio has a true mind map collection figure but we don't currently offer a general concept map container. However, they can be easily constructed using Curio's attached text functionality which we added back in Curio 6.4.
Simply by holding down special modify keys (Command, Option, Shift) and clicking you can expand your map with connected figures. This is a fast and fun way to brainstorm in a freeform way, without the formality of a mind map, directly within Curio.
And attached text was recently improved in Curio 8.2:
If a selected figure is a freeform-sized figure, then when creating an attached figure (by holding Command or Command-Option or Command-Shift and clicking), Curio will now make the new attached figure a freeform-sized figure of the same size.and
After creating an attached figure we no longer auto-remove the figure if you don't type something into it at that time.This makes certain types of freeform thinking maps, such as bubble and double-bubble maps, much easier to produce. Curio now includes examples of both as bundled figure stencils.
Happy brainstorming!