Cyccommute, I have a bashguard on a different bike right now. It's a similarly set up drive—two chainrings and that bashguard on a triple crank, but with a seven speed cassette. And when I'm in the highest gear, the chain rubs against the bashguard. So that's why I was asking about the chain line—it's a problem I've had before.
Also, this is the second time since installing the VO chainguard that I've had to repack that bottom bracket. And the grease on the drive side was fouled, but the grease on the NDS was perfectly clean. So I'm going to try a solution that doesn't involve fitting something under the fixed cup. And if after a few more months of rain riding, my bottom bracket starts grinding again, I'll know it wasn't the VO part. But I strongly suspect it was a less than perfect fit.
Though if that doesn't work, I'll probably take your advice and get a sealed cartridge bearing BB.