Yes mention of asteroids should appear in the config like this once you visit the Asteroids and ONLY once you visit them:
As for that Worldgen Crash Issue, are you secretly using some world pregeneration mod of the sorts?
No, no extra mods.
Only gregtech_1.7.10-6.11.05, Galacticraft 501 and Forge 1614. Even the configuration files left by default