Is it possible to set value in script parameter in SS1.0, I'm trying below but no luck

nlapiGetContext().setSetting('SCRIPT', 'custscript_ps_asnlastid',lastID);

I believe setSetting is for session objects, not script parameters, thats what the help documentation seems to indicate to me https://system.netsuite.com/app/help/helpcenter.nl?fid=section_N3077939.html#bridgehead_N3083382

right, actually I have a schedule script and i'm trying to set parameter after its completion

you can update the script deployment record