Strategic combat - a couple of Newby questions

[Growltigga]

what is with this strategic combat lark? I have tried it on my first SE IV game but everything blitzes around so darned fast you dont seem to be able to influence it in any way. Also, various threads seem to say there is a playback mechanism but I cant find that anywhere - can someone please tell me what this strategic combat bit is?

one more question, what do the explore and sentry buttons do - given that you can see the whole system as soon as you enter it, the explore doesn't seem any use - I am not sure what the purpose of the sentry is either as it doesnt seem to make any difference

Any assistance or sarcastic remarks greatly appreciated