Fluxbox on AIX 5.1 ORLY?!

Hello List,

I hope some people still use AIX for retro fun purposes and can help me 
out.

I have installed flux on AIX 5.1 to replace the ugly CWM.

I have tried:

fluxbox-1.3.5-1.aix5.1.ppc.rpm

fluxbox-1.3.3-1.aix5.1.ppc.rpm

But gave up after the following graphical errors:

https://ibb.co/qBn53Ls

I have tried other styles as well its the same result. Probably would be 
the same with all.
Is anyone have an idea what is going on here?

Thanks