The Slovenian is maybe more a Croatian then a Slovenian.
They both share the letters, but Croatian alphabet has Ć and Đ officially in it, while Slovenian doesn’t.
Slovene alphabet - Wikipedia for Slovenian
Gaj's Latin alphabet - Wikipedia for Croatian
Keyboard layout is fine. I have a Logitech keyboard with Croatian layout that also has International English signs on Č, Ć, Ž, Š and Đ signs (and on , . -) which is really nice if you want to use English layout also.
All in all it’s ok and you can market it as Slovenian/Croatian