A few questions as never heard of cross threading before or never done it 

The question is that if you can do it up by hand the bolt all the way to till the end of the internal thread female end in the engine and then can tighten it up its fine with a spanner until it stops 

If a bolt had a slight resistant, then on the next turn it was easy to turn and then all the turns all the way up to the end was easy then is it okay or if the same situation occurred again on the same bolt and still went easy on the turns afterwards is it okay until the end.

Is cross threading where your stripping the bolts at a angle as misaligned and also where the male bolt the tip of it is touching the side of the wall on  the female thread and it hard to turn as the tip of the male thread is trying to go though the metal hope that makes sense in order to maintain that angle . Which will cause pressure and could cause it to snap as it will bend the bolt and also bend the threads causing stress and allot of force from whoever turning it . Hope this makes sense.

I know this is old but I only just realised after typing all this out lol!

I always understood cross threading to mean that the bolt hasn't engaged properly with the female thread so what you're doing is chewing either or both of the threads. The harder metal will destroy the softer.

I think it's more common on double threaded bolts, where there are 2 threads to engage, 180 degrees apart around the bolt. What happens there is that the bolt will seem to start nicely on one thread but miss engaging on the second thread until the next half turn. If the thread is fine enough then what happens is the bolt feels nice and loose to start with but is actually entering at a slight angle. It will start to 'tighten' prematurely, and then force will be used to nip it up. Unfortunately this is where one thread will chew the other, then the bolt will feel loose again until it reaches its actual bite point.