You should find the kernel is just a drop in replacement for the v7 code - one slight difference might be that mutexes cannot be used from interrupts any more due to the way priority inheritance works. If there are any differences it will be with the tools, rather than the C code.
Are you saying creating a task after the scheduler has already started is causing the hard fault? It sounds like it because you say the tick interrupt is running. If that is the case then creating a task is not the issue in itself as you will already have created at least the idle task with an issue. Therefore your problem might be that you are simply running our of heap, or something like that.
When you step into the code in the debugger, at which point does it crash?
Are you sure it is crashing in the task create function, and not in the task you are creating - as that task may execute before the task create function exits.
Have you done everything recommended here?