I has model Obj change rename blb and I did open it and I see nothing, just black.
-snip-
1: If you read, he's still adding support for it and others.
2: That's not how changing formats worked. If it was, you would be able to make movies into animated gifs by changing .wmv to .gif.
Realize that the filetype . listed is simply to specify what kind of file it is. Changing that won't magically change how it's formatted.