I created some shapes with the pen tool and then with the brush, but when I switched back to pen tool I couldn't change the stroke.
I can't change its colour or make it transparent either. Does anybody have an idea what went wrong?
Check your Appearance Panel. There may be a stroke applied there. You may need to highlight the stroke in the Appearance Panel before attempting to change it.
You need to select the elements in the dartboard that you want to wait before changing the color in the toolbar. Try clicking on your black line then removing the stroke in the toolbar.
I know this is an old thread, but in case anyone winds up here looking for answers, I had this same problem with a project where I used the pen tool and then used live paint to fill in the shapes individually. If you go to Window>Appearance then select your lines, then click Add New Stroke (the box on the far left of the Appearance tab that pops up), you should get all of your strokes back. This allowed me to use brush packs again, which it was preventing before. Hope that helps!
Open the "Brushes Palette" and locate the brush you want to edit. Double click on the brush to open the "Settings" menu for that brush. Click the drop-down menu labeled "Colorization" and select the option "Tints." The color of the brush will now be determined by the selected stroke color.
I had an issue where I couldn't change the colour. Livepaint was just not working and it drove me up the wall. Then I went into View>Overprint preview, and suddenly I could add colour...