Game design environments are traditionally used as means for engaging non-programmers in the learning process. However, these environments lack specific support for teaching computational thinking to novices. Typically, such skills are acquired in ad hoc practical sessions with supervision provided by teachers or peers. The usual scenario is where a teacher guides the students in solving these problems during a game design session. In informal learning settings, step-by-step tutorials for creating existing games are used to compensate for the lack of computer support for solving design and computational problems. In this paper we suggest a game design process that combines support for computational thinking with tool usage, by identifying the most common computational thinking problems and providing a generic solution to them. We have evaluated our solution in the context of AgentWeb, an online cloud-based game design environment for novices. We discuss how to incorporate suggested computational thinking solutions as computer assistant into the game design user interface.