For a segmentation fault, you should check your user stack limit setting, and, for a large case, your thread stack limit (default 2MB for 32-bit, 4MB for 64-bit, adjustable according to KMP_STACKSIZE).
The best way to report this is by filing a problem report with (if possible) a small reproducer on premier.intel.com. Registering your license automatically creates your support account. If you didn't register it, you can do so at
https://registrationcenter.intel.com.
I have a stale bug report in about failure of collapse. Recently, one of my customers had some success with collapse, even in a case where the outer loop count isn't fixed at compile time and there is a vectorizable dot product inside the 2 outer collapsed loops.