How to CHANGE existing models instead of only read or write?

I just want to know if I can change a model, deleting some entities, faces and vertices, creating new ones and save the model to same skp file.

I only found functions for reading an existing model, or for writing a new one.

Thanks

There are currently no functions to remove entities. But you can add new ones (SUEntitiesAdd* or SUEntitiesFill) and save the file.