Singapore import ..code readings.

My 97 E200 is imported from singapore.Im in New Zealand .Every time we try to get code readings from my mates device ,it wont let us in due to it being from singapore.He says different software .Nearest merc dealership is 5 hours drive away.They say they are the only people who have the right software to read singapore imports.My friend device gets in but when it scans it seems to just stop workin or boot us out....If anyone knows a way around this or just has something to add ..please do......Im a novice ....