This is great! I would suggest adding (possibly customizable) keyboard shortcuts, for saving and running, etc.
You can press ctrl+s to save and while holding control, you can press the minus and plus button to change font size. You can also quickly load text and bf files by dragging them onto the ide.
Thanks for your feedback! Although I'm not sure if I'll make these shortcuts customizable since that would be a lot of work and I'm not really interested in working on BF Designer anymore.