File generated can not be opened by Sketch
### Description

The file generated by Kactus is not opening on Sketch. Seems that the "Export Sketch File" is working, but when I remove the file created by Sketch and do the "Regenerate Sketch File" it is not opening.

### Version

**Kactus version:** 0.1.12

**OS version:** 10.12.5

### Steps to Reproduce

I have pushed the design here: https://github.com/Adventech/design

1.  Open Kactus and "Regenerate Sketch File";
2. Try to open the generated file.

**Expected behavior:** Open the generated file on Sketch

**Actual behavior:** Cannot open the file

**Reproduces how often:** Always

**UPDATE**
I have also tried with **Kactus version:** 0.1.13, now it is not even generating the Sketch file.