put the tree model in C:\tree.3ds
Thanks very much ! This hint was really helpful and works perfectly for me with the .3ds files.
Even the exported .obj file from the Tree Maker has been converted, though TV Model Conversion Util got a timeout while converting ...anyway, the exported tree.tvm shows up in C:\ ... with a file size of 80 mb.
TV Model Viewer nearly freezes my machine after opening that file and took 200 megs of RAM

So, as others mentioned before, the tree files are too big .
so what should be done: just put quotes around the path (dunno if it works in the modelconverter, just try that).
The funny thing is, while putting the path into quotes, the TV Conversion Util disables the Convert button

Greets