They have to pay out your annual leave entitlements, and if your work at that company addes up to equivalent of 7 years full time or greater, they also have to pay out pro rata LSL entitlements.

There is no requirement for them to pay you for unused sick leave accruals.

I would be getting some advice, it doesnt sound altogether legal what they have done to you, they've tried to force you to full time and then fired you becaause you said no?