On the event website: http://indico.ijs.si/conferenceDisplay.py?confId=886
Please follow the link "Apply here" to register for the event before 2 April 2018.
The timetable is preliminary and will evolve.
April is not high season for Ljubljana so you should get a good rate in either a hotel or e.g. AirBnB.
Few hotels are listed here, or check on the internet.
Taxi is a good option to get you from the Airport to Cosylab. Trip takes ~30 min and costs around ~25€.
Order the taxi* before arrival to avoid waiting http://www.taxi-intertours.si/
(*Taxis available in front of arrivals exit are normally double price)