It's still possible to jump onto boxes in de_dust2, as long as you use a crouch jump.
As far as tweaking the code goes, I may be able to make changes in future, when I know more about the code, and how it works.
Please, bear in mind, that I dived in at the deep end, and only started learning this 3 days ago. There is loads to learn, so hopefully, I can bring out updates to this plugin in future.
Hope you like it, and thanks for your suggestion.