Running the provided examples, I was getting Warning: Could not load network parameter file!.
It states in the documentation that the net_params should be provided as a .JSON file, but the examples are given as .txt (although in JSON format). Re-saving it as a JSON file did not solve the issue. However, looking into the MiMeNet source code, I saw the hyper parameter for learning rate is denoted learning_rate in the hyper parameter file but lr in the source code, so fixing that resolved the issue.
{
"num_layer": 1,
"layer_nodes": 128.0,
"l1": 1e-03,
"l2": 1e-03,
"dropout": 0.25,
"lr": 0.0001
}