Don't know if you figured this out or not but I wanted to do the same thing so figured I would put the answer here for you or others who may want to do this. It really quite easy.

You need to create a template for the proforms_list. Create a new folder in /blocks called proforms_list then inside that create a folder called templates. Should end with something like this: /blocks/profroms_list/templates. You then make a copy of /packages/proforms/blocks/proforms_list/view.php in the newly created templates directory and rename it to something like my_list.php. Note: that whatever you name the file is how it is going to show up in the list of custom templates later.

Now open up that file and around line 51-53 you are going to see a <th> container that has the code for the ID# column header. Look for "ProformsItemID". Delete that from the table. Now below that around line 79 (before you make the above edit) You are going to see remove that. Save the file and if you where doing this locally make sure and upload to your server.

Now after you add a ProForms List block you'll be able to choose this new Custom Template to use! Remember it is going to show up how ever you named it. i.e. My List.