few concerns here on how you handle rest services in tiggzico.js
1) cache: true - that's asking for problems and reason why I was having issues with cached REST services, default should be set to FALSE so you let user decide on server side how to handle cache
2) timeout: 20000 - that's an overkill 
20 seconds is REALLY bad idea...
proto.requestDefaults = {
dataType: "json",
type: "get",
cache: true,
crossDomain: true,
timeout: 20000,
traditional: true
};