Full marks for posting your errors completely. 
Zero marks for not showing your code and other pertinent material. 
All your errors surround the “verify” APIs. Did you try “wait” APIs?
- https://docs.katalon.com/katalon-studio/docs/webui-wait-for-element-present.html
- https://docs.katalon.com/katalon-studio/docs/webui-wait-for-element-visible.html
In future, please follow the advice given here: