Fit to Experiment error

[espooner]

Hello- when I try and use the 'fit to experiment' button, e.g. to fit a modelled JV curve to a real one, nothing happens. I can see a blank 'fit the simulation' tab when I switch between windows, but this never loads, and I can't get it to stay on the screen. The help window for fitting pops up sometimes. Any tips would be welcomed, thank you.