No, the style you use applies to the whole of the VTP you modify.

But each VTP can be given a different style so long as they do not join eg 2 lakes in the same LOD 13 cell can be given different characteristics eg sand shore with waves, black shore no waves

Roger

PS

I've just realised this may not be what you are asking. Yes, you can edit your work afterwards using eg Wordpad or Notepad to change the characteristics (but subject to what I said above). You edit the asm file and then recompile.