Irrevocable Resignation with a Foreign Employer

Hi I'm just new here, I would like to seek some advice with regards with my previous job. I worked for a Singaporean Company which has no business operating permit yet here in Manila and gave me an employment contract which is not registered in Ministry of Manpower in Singapore (technically speaking that contract is between me and the company only). Recently I quit and my reason is irrevocable, now my employer didn't want me to pay my last salary what I did was I hold some company properties. My previous employer telling me that she will be prosecuting me using her contacts in Singapore. Please help me about my rights and on what to do, I really just want to get my last salary 'coz I worked hard for that.
I'll be waiting for your advise. Thank you.