> My question was not intended to attack the operating system,
> but rather to try and find where I was going wrong - I'll
> let you all know when I find the problem.

You may do what I did:
Compile to assembler source code, and then examine it.
If you find stuff like: 
a <- b * c
a <- a + d

Then you have bad code. Fast code should look something like:
a <- b * c
e <- Array[x]
a <- a + d

I.e. interlieve instructions.

Kim0