jqgrid is nice product and sometimes, well, really when it comes to forms, you really got to fight with it and read. I have pretty much come to a cross roads with jqgrid and form editing. It is great on the grid side, but forms, just to many probs and not clear enough info. I have been trying to figure out for days how to catch the dataurl error. Wine wine wine 🙂
Ultimately, just decided to just start building my own forms and stop using jqgrid native forms for edits, except for the most simplest of forms.
Look up custom buttons in the wiki, you can search for it. Also google jqgrid custom buttons. There is info out there. Not sure about passing the grid data to a form. I am just calling ajax event to load data.
Jqgrid can be pretty frustrating when your first starting out if you want to do anything more then just the basic form. Once you learn the ropes, you can see what a dynamic product it really is.
Good Luck