Whats the Problem?

Ok so heres the deal, I have a '91 Civic LX 1.3 European Model, as I'm In Ireland. Ive been going to college everyday for the past 3 months, its around 30 miles, with lots of traffic on the way. Over the past month roughly my car had been having problems, I started cutting out in the traffic when the engine was at normal temp and when it was at various others. Its usually when im changing down. One morning it started doing it and i went to restart it and the battery was fully dead. I brought it to the garage for a full service, they retuned the whole engine @ 126000 miles, (last week) The last few days it has been cutting out but not as bad, it only will do it once now, and its fine again, the garage also said its charging fine and they checked all that at the service. I usually have the radio on and sidelights and sometimes the heater. I have noticed it is hard to change into 2nd gear sometimes, what could the problem, be is it electrical? the garage doesnt seem to know, and they are a honda dealer. Hope you read down this far, please help, Alan

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