K2 Workflow Effort Estimation

you are confused in effort estimation of k2 workflow
This post would help you in this . K2 does not have any guidelines on this till now ..
Check this post in couple of days..

K2 Issues and Resolution

Problem: Issue with K2 worklist . Its coming blank
Solution: Account from which SharePoint is running should have impersonate access in k2. This access can be provided from k2 workspace