while Caarrie says it *can* cause issues, it *does* work. I have a PPC-Mac, too. And I replaced all the problematic maps with the ones from 0.4.01. So far I haven't had any problems. As far as I see it, the problematic maps are these:
bdroad1.zip
bdroad2.zip
bronzedoors.zip
gugrontid.zip
hydlaa_jayose.zip (not quite sure if that is really a problematic map though)
ojaroad1.zip
ojaroad2.zip
I have been using those maps for some weeks now with the 0.4.02-client. The only issue I have is that when I try to get from the first part of bdroad (the one after Hydlaa) onto the second part, the client often crashes. And when I relog I am placed back on the map I came from. But *sometimes* (after trying to enter the other bdroadmap a few times) my character is placed on the second bdroadmap, so I can finally enter bronzedoors as well. The only thing is that this second bdroad is unbelievable laggy. But bronzedoors itself is just fine.