the only way that the lights not flashing on the dash is linked to the roof is if the issue is a faulty ignition switch
if not a faulty ignition switch, then there is very little chance these issues are connected.
the EML light comes on when there is a problem with the engines electronic throttle control system. Whoever told you the roof, or the lights, could trigger an EML light simply does not know what they are talking about.
I would not buy this car until the issue is fixed. It could be just an ignition switch, but it could be MUCH worse if there is a roof issue. Roof issues are NOT fixable at home. You will be paying BMW workshop labor prices for any roof repair.
this car sounds very sketchy and I would stay away unless everything is fixed and you have can the car inspected by a qualified third party mechanic prior to purchase
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