the problem is the BOM some editors save the utf-8 with.
this gives you 3 additional chars you don't see in the editor!
Which editor are you using?
you can try to open the twg.lic.php in the editor of the TWGXplorer - then edit it - I think there is shows the 3 characters - remove them an save them again.
Or update TWG to the latest build - there I updated some files that prevented output exactly because of this. if you download the latest version check the version.txt. there you find what files to update.
If you are interested what BOM is:
#removed_broken_link
(there they tell you about this problem too)
/Michael