Hi Travis Chambers,
We have checked the issue by importing the charts with primary and secondary axis. But we were unable to reproduce the issue, it loads fine. Henceforth, can you please update us the excel file which reproduces the issue so that it will be helpful for us to analyze the issue better and update you with appropriate solution.
Regarding Shadow issue,
We regret to let you know that currently SfSpreadsheet does not have support to import the shadows in chart. However, we have added it to our feature request list, and
this feature will be included in 2017 Vol1 release.
Regards Kanimozhi B