If you have Acrobat Pro you can edit a pdf form file to have the various field border properties that you describe. You would create the form in FormsCentral and save as PDF. Then you would do a Save a Copy on the form. Open the copy and select Tools->Form->Edit. You can then select the fields and set the border in the Properties dialog in the appearance tab. Once you have the form looking the way you want you would then re-import the copy into FormsCentral and send the file out to the world.
Hi Jeff, thanks for the reply.
I have Acrobat Pro - but I don't get it to work properly. It seems I somwhow have to avoid the security settings to be able to edit the new document? Any suggestions?
I found the solution - thanks again ;-)