The style files allprose.sty.nw and myalps.sty.nw can be locally modified through the file local.sty.
The content of the file should never define a new command but rather modify existing ones so that the output might look more colorful, for example. In the ALLPROSE framework the file local.sty is completely optional.
See the targets rm-local.sty, laptop, screen, colored, no-srcltx to see how local.sty can be used.