I spotted a few more incorrect garbage collection links and all of those should be fixed in 0.8. The plugin version definitely says 0.8 so you may not have correctly replaced the plugin. Remember that you need to delete the old plugin content/plugin source to replace it as some classes have been removed.
If you’re still getting an issue, try to narrow the function call as much as you can. I believe yours seems to be due to the controller->frame releasing the object early which should have been fixed in the last update.
I’ve been using the 0.8 version in the leapjam and it’s been stable while using the circle gesture detection for quite some time, way beyond the GC interval. Let me know how it goes!