Convert Polyline to MultiGeometry

[shannon9585]

I have a shapefile that consists of polylines. I want to convert them
into KML using <MultiGeometry> so that there is only one <Placemark>
for each feature. I also want to be able to create a customized
information balloon using the <ExtendedData> element. Are there any
free shapefile to KML converters that do this? Or, is there some
other easy way to do this?

I like the Export To KML ArcScript for creating customized information
balloons, but it creates a KML without <MultiGeometry> (so each
segment of each polyline is a different <Placemark>, which isn't what
I want). I've also used the Shp2KML tool from zonums to create KMLs
using <MultiGeometry> and have manually edited the code to customize
the balloons, but for some reason this tool isn't working for me now
and the download isn't working on their website.

Any ideas?