I think the issue was by ths following , I've made a scaled down app in a single script to specifically tackle this problem. Code paste is

. , The problematic code is here:

code :

```
def load_ROI_table(self):
...
roi_names = [roi_table[x, 0] for x in roi_table_range]
print(roi_names)
```

```
['AC', 'V1', 'M2', 'BC', 'RS', 'M1', 'HL', 'HL2', 'HL3']
```

```
print(['%s %r' % (type(i), i) for i in roi_names])
...
["<class 'numpy.str_'> 'AC'", "<class 'numpy.str_'> 'V1'", "<class 'numpy.str_'> 'M2'", "<class 'numpy.str_'> 'BC'", "<class 'numpy.str_'> 'RS'", "<class 'numpy.str_'> 'M1'", "<class 'numpy.str_'> 'HL'", "<class 'numpy.str_'> 'HL2'", "<class 'numpy.str_'> 'HL3'"]
```

```
roi_names = [str(roi_table[x, 0]) for x in roi_table_range]
```