How to Generate Control flow graph from a Petri net model?
Since you are interested in generating test sequences automatically using colored Petri nets, note that it's not clear that you need reduction to control flow graphs (and dealing with all the related issues). Some techniques were presented, that use various different methods to generate test sequences from Petri nets. Some examples include:

H. Watanabe and T. Kudoh, "Test suite generation methods for concurrent systems based on coloured Petri nets," Software Engineering Conference, 1995. Proceedings., 1995 Asia Pacific, Brisbane, Qld., 1995, pp. 242-251.

J. Desel, A. Oberweis, T. Zimmer and G. Zimmermann, "Validation of information system models: Petri nets and test case generation," Systems, Man, and Cybernetics, 1997. Computational Cybernetics and Simulation., Orlando, FL, 1997, pp. 3401-3406 vol.4.

Xu, Dianxiang. "A tool for automated test code generation from high-level Petri nets." Applications and Theory of Petri Nets. Springer Berlin Heidelberg, 2011. 308-317.

On the other hand, since Petri nets and control flow graphs are not semantically equivalent in general (and capture different type of information), the translation between the two is usually done in some specific domain (and restrictions). (Although usually, control flow graphs can be transformed into equivalent Petri nets.). Some examples and discussions are given in:

De Jong, Gjalt G. "Data flow graphs: system specification with the most unrestricted semantics." Proceedings of the conference on European design automation. IEEE Computer Society Press, 1991.

The Design Of A General Method For Constructing Coupled Scientific Simulations, Matthew J. Sottile

Note that your question seems a bit too general. (Moreover, it also seems as an instance of XY, as noted by D.W.) Without more details, it seems hard to give a concrete and concise answer. Hopefully, given pointers can get you closer to your desired goal.