chooseFolder.js

var properties = PropertiesService.getScriptProperties();
var TARGET_ROOT_ID = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"; // ルート
var TARGET_FREQ_ID = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"; // よく更新されるフォルダ
var rootFolder = DriveApp.getFolderById(TARGET_ROOT_ID);
var ct = properties.getProperty('updateCheck.rootContinuationToken');
var itr = ct ? DriveApp.continueFolderIterator(ct) : rootFolder.getFolders();
var id;
do{
    if(itr.hasNext()){
        // つぎのフォルダがある
        targetFolder = itr.next();			
    }else{
        // つぎのフォルダはない
        itr = rootFolder.getFolders();
    }
    id = targetFolder.getId();
} while(id == TARGET_FREQ_ID || JSON.parse(properties.getProperty('updateCheck.muteFolderList')).indexOf(id)!=1)
properties.setProperty('updateCheck.rootContinuationToken', itr.getContinuationToken());