The light-trail architecture provides a novel solution to address IP-centric issues at the optical layer. By incorporating drop and continue functionality, overlaid with a lightweight control protocol, light-trails enable efficient sharing of network resources, support subwavelength traffic and minimize costs. In this work, we investigate network design and survivability issues in such networks in the presence of multi-granularity subwavelength traffic subject to nonbifurcation constraints. We first establish the NP-Hardness of the light-trail routing problem by reduction from a Hamiltonian path problem. We propose three heuristics for lighttrail network design and study their performance with limited network resources. We observe the effect of tunable and fixed transceiver equipment on network throughput. We observe that our heuristics yield excellent wavelength utilization under moderate to high loads even in the presence of heavily fractional traffic.We propose two additional heuristics for shared and dedicated protection and conclude that with only a modest amount of spare capacity, full protection can be achieved for all single link failures.