Thanks for replying fingertrouble, much appreciated.
While I realise that I am using a flight simulator, I still aim for realism so it's good to understand how things work with SD.
Re: 3, I have got better at planning over the last 2 weeks, this isn't my first rodeo but I did need to get back into the saddle again, so completely understand why this isn't needed. I also have a TOD marker on my GTNXi 750 unit, so it's not necessary, I also calculate my descent, like any real pilot!
I was asking about the altitude change but realised after reading your reply that you're right and it's totally not necessary, the direction remains the same!
Thank you for your help and advice, fly safe!
Toby