[pluggo] Waveform~ not drawing correctly in Plug-in

I've made Pluggos on PC before, but this time I'm trying to do it on a Mac and running into problems. The biggest issue right now is that the waveform~ object isn't drawing correctly. When an area is "selected" it becomes hidden underneath an opaque black box instead of visible underneath a translucent blue. 

I'm using the newest version of Pluggo and Max/MSP as of June 18, 2007. I'm on a Mac Mini Core Duo, testing the Plug-in inside of Ableton Live. I have the exact same patch running as a Pluggo on my PC with no graphics problems.