THBB HighC is not PPC only. This is a bug in MacUpdate automated analysis of the application bundle, and I can't fix it from my developer's page.
HighC is a Java application, and thus works natively (modulo the java runtime) on both Intel and PPC architectures.
For those interested in the details: In order to function properly on all platforms from 10.3.9 to 10.5 and above, I have to include a PPC-only java application stub. This stub is recognized by the OS on Intel platform, and not used. On older platforms, only this stub will work, not the newer fat binaries...
(Version 2.4)