I took a look at your project and I couldn't replicate your issue with our latest version of ShinobiCharts (2.5.6). Could I ask what version of charts you are using?
It looks like an issue we had when Apple first released their 64bit hardware, which we fixed in our 2.5.4 release - I can't be 100% sure though. Could you try updating to a newer version of charts that contains this fix? If this doesn't fix the problem, please let us know and we'll investigate further.