Finicky model reference in accelerator mode

I have a Simulink model (let's call it "parent") which has a referenced model (let's call it "child"). The model "child" has one inport and one outport, both defined by the same bus object; "child" can run in normal or accelerator mode (though its outputs are meaningless when run alone). When I add "child" as a Model block (i.e. model reference) in "parent" and try to run it in Accelerator mode (both the Model block's simulation mode and the simulation mode for "parent") I get the following errors in Simulink's Diagnostic Viewer (running release 14a right now):

    Error:  Simulink Coder Error: Nonfinite value in structure parameter is not supported
    Component: Simulink | Category: Model error

    Error while bringing model references of model untitled up to date:  see errors reported above for details.
    Component: Simulink | Category: Model error|

I can't seem to find much on this error. However, if I switch "parent" and its Model block to run in Normal mode, then the thing runs just fine.

I am unfortunately unable to share the model, but does anyone have any ideas what might be causing this error when attempting to run in Accelerator mode? Or does anyone have a suggestion on how to debug this issue? I can get the same errors by simply updating the diagram on "parent" but can't figure out how to get any further hints as to what might be causing problems.