Automatic replacement of specific ligatures in OTF font


We have created a specfic font, in OTF format, with purpose to beneficiate of the automatic replacement of some specfic letters, based on its position in the word.
For example, in this script font, the letter “s” is different if placed at the end of a word.

It works fine with LibreOffice (4.2 or 4.4) under Ubuntu, but the replacement does note take place automatically with the Windows version of LibreOffice.

Any idea where the problem might come from?
Thanx for any advise