Model Based Testing (MBT) is a popularly used software testing technique in the software industry. However, there still exists a gap between the awareness of benefits of MBT and its adoption in the industry, specifically in the Computer Aided Design (CAD) or Computer Aided Engineering (CAE) domains. This can be predominantly attributed to the learning curve of using many of the existing MBT tools. To address this gap in the CAD/CAE industry, we propose Pathfinder-an MBT tool, with a Graphical User Interface (GUI), for guiding a software tester in generating test plans for a system-under-test (SUT). The goal of using Pathfinder is for obtaining consistency and reproducibility in the generated test plans across a team of software testers. Our tool introduces a novel representation of the SUT as a High-level Model (HLM), and the use of graph visualization for test plan generation from the HLM. We have designed the GUI to be intuitive for the tester to generate test plans and select relevant tests, which precedes the test execution done outside of our tool. Here, we discuss the design decisions we adopted towards creating Pathfinder, and demonstrates its usage with two case studies.