Just to jump back to the Tyros.
For anyone interested in importing samples, Extreme Sample Converter supports converting from many different formats to Tyros 2 format.
Once you get the data to Tyros 2 format you can use the normal free tools available to get the data to Tyros 4 format.
http://www.extranslator.com/ Extreme Sample Converter also has the ability so extract sounds from VSTi's and convert them to Tyros sounds.... and much more.
Regards
James