the main issue is that the game consumes a lot of cpu usage when it is idle, which reduces the time until my netbook must visit its power station

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But this is not a complain at all...the code is older than a decade and for sure not changeable regarding this matter.
If you write (new) software today, you have to take mobility into account (android/ipad os as an example)...BTW winspmbt2 running on android (tablet pc) would be just cool
