I have been using the previous version which whined about 'no Altivec' everytime I opened it, so I was glad to see this warning is gone in this version. However, all other functionality appears to have disappeared too.

Nothing happens when I click the 'play' button or when I open a file. When I try to add something to the playlist, it crashes.
I did some diagnostics by replacing the 'mplayer' and 'mplayer_noaltivec' binaries in the application package with bash scripts which dump their arguments in a file. They aren't even executed when a file is played or opened, only when adding something to the playlist. So when I say that 'nothing happens' when clicking 'Play', I really mean nothing.

Assuming that the 'play' button would work, I still wouldn't have playback. When I run the 'mplayer_noaltivec' binary in the terminal, I get
"dyld: incompatible cpu-subtype
Trace/BPT trap"
After replacing mplayer_noaltivec with a working self-compiled binary, adding stuff to the playlist still causes a crash, so this thing is broken beyond repair. I suppose I'll have to cope with the 'no altivec' warning until the first major revision of the MBP is available.

I know the developer has no access to a G3, but that doesn't mean that other people with a G3 -- like me -- can beta test...