The goal of this research is to improve the programmability of DNA-based computers. Novel clockable microreactors can be connected in various ways to solve combinatorial optimisation problems, such as Maximum Clique or 3-SAT. This work demonstrates by construction how one micro-reactor design can be programmed optically to solve any instance of Maximum Clique up to its given maximum size (N). It reports on an implementation of the concept proposed previously [1]. The advantage of this design is that it is generically programmable. This contrasts with conventional DNA computing where the individual sequence of biochemical operations depends on the specific problem. Presently, in ongoing research, we are solving a graph for the Maximum Clique problem with N = 6 nodes and have completed the design of a micro-reactor for N = 20. Furthermore, the design of the DNA solution space will be presented, with solutions encoded in customised word-structured sequences.