got around it like this:
Dim script As String =
"var element=document.getElementById('MYFORM');"
"var input=document.createElement('input');"
"input.type='submit';"
"input.setAttribute('id', 'submit');"
"element.appendChild(input);"
scraper.Actions.InvokeScript(script)
Dim submit As Element = scraper.find.byid("submit")
scraper.Actions.Click(submit)