Is this only happening to me? Is it a known bug? I don't remeber this happening to the older versions.
When there is no background, the shape layers glitch out, and sometime the whole program crashes. If there is a solid fill background, it workds fine.
I haven't had any issues like this with shape layers. Have you tried rebooting or resetting your preferences? Hold Ctrl+Alt+Shift (Windows) or Command+Option+Shift (macOS) while starting After Effects.