Re: SKOS tools?

You can use TopBraid Composer Free Edition [1] to edit any RDF/OWL  
model, including SKOS instance files. I have attached a screenshot  
(not sure if it gets through). A key feature is to use the Association  
View (shown on the left) to display SKOS semantic relations such as  
broader in a tree. Then the usual forms can be used to fill in the  
details of each concept, including multi-lingual labels.

Holger

[1] http://topquadrant.com/products/TB_free_download.html