require(['N/runtime',
	'N/search',
	'N/render',
	'N/record'],
function(runtime, search, render, record) 
{
function addUserNote (options) {
		var note = record.create({ 'type' : record.Type.NOTE });
		var finalContent = '';
		if ('title' in options) {
			finalContent += runtime.getCurrentScript().id;
			finalContent += ':';
		} // else this will become the title so skip
		finalContent += runtime.getCurrentScript().deploymentId;
		if ('note' in options) {
			finalContent += ' ';
			finalContent += options['note'];
		} // else no note but use script details
		if ('transactionID' in options) {
			note.setValue({ 'fieldId' : 'transaction', 'value' : options['transactionID'] });
		} else if ('customerID' in options) {
			note.setValue({ 'fieldId' : 'entity', 'value' : options['customerID'] });
		} else if ('recordID' in options) {
			note.setValue({ 'fieldId' : 'record', 'value' : options['recordID'] });
			if ('recordType' in options) note.setValue({ 'fieldId' : 'recordType', 'value' : options['recordType'] });
		}
		if (!('transactionID' in options) // transaction user-note
			&& !('customerID' in options) // customer user-note
			&& !('recordID' in options) // custom-record user-note
			&& !('recordType' in options)) throw finalContent; // should not happen but just as defensive code
		if (finalContent.length > 4000) {
			finalContent = finalContent.substring(0, 4000);
		} // else the entire note fits the maximum User Note memo length
		note.setValue({ 'fieldId' : 'note', 'value' : finalContent });
		if (!('title' in options)) { // default the title
			options['title'] = runtime.getCurrentScript().id
		} // else use the title provided
		note.setValue({ 'fieldId' : 'title', 'value' : options['title'] });
		note.setValue({ 'fieldId' : 'direction', 'value' : 1 }); // i.e. "Incoming"
		note.setValue({ 'fieldId' : 'notetype', 'value' : 7 }); // i.e. "User" - Setup > Sales > CRM Lists > New > Note Type
		return note.save();
	}
	var snapshotID = 3380709;
	var recordType = 'customrecord_v4_render_snapshot';
	var recordTypeID = 807;
	addUserNote({
		'title' : 'Sample 1',
		'recordType' : recordType,
		'recordID' : snapshotID,
	});
	addUserNote({
		'title' : 'Sample 2',
		'recordType' : recordTypeID,
		'recordID' : snapshotID,
	});
	addUserNote({
		'title' : 'Sample 3',
		'recordID' : record.load({ // reuse custom record
				'type' : recordType,
				'id' : snapshotID	}),
	});
});

recordtype

record

"123"