Day after day, we discover new ways to use computation in various domains and for a variety of purposes: entertainment, medicine, education, communication, etc. Large-scale hardware production has made computers and mobile devices (for example, cell phones, PDAs and Tablet PCs) more accessible to an increasing number of users. The wide use of computation requires software to be developed not just with high internal and functional quality, but also with high quality of use. In face of this need, Human Computer-Interaction (HCI) researchers have researched ways to design user interface with high quality of use. In particular, some HCI researchers propose model-based user interface design. Paula (Paula, 2003) proposed the MoLIC language (Modeling Language for Interaction as Conversation) to model the human-computer interaction, grounded on semiotic engineering (de Souza, 2005). Since its proposal, MoLIC has been used in case studies in different domains and platforms. These studies have raised questions about the use of the language that have remained unsuitable or that still had not been addressed in the first edition of the language. Some of these questions gave rise to extension proposals to MoLIC. As there are still opened questions raised from these case studies and the extension proposals were not sufficiently sound to be definitely incorporated into MoLIC, there was the need of a work to address those questions and to organize the extensions, as well as additional proposals that may be found necessary, with the concern of keeping the language consistent with its theoretical grounding. Therefore, this work presents a revision of the first edition of MoLIC, pointing out and answering open issues. As a result of the revision, it defines the second edition of MoLIC, which incorporates several extension proposals. And, finally, it concludes by raising additional questions to be addressed in future MoLIC editions.