In Wolf4SDL, this should be as easy as just increasing the MAXACTORS and MAXSTATS definitions in WL_DEF.H.
What about the DOS version. Can you also do this or does something else need to be done?
I believe that works too, although it will increase the amount of near bytes used. Mind you, if you're developing for the DOS version these days, expecting to be able to do that sort of thing as easily as the SDL version is probably a forlorn hope.