I noticed that the recurring payments name is defined differently than

I noticed that the recurring payments name is defined differently than the other elements within an Authorize.net widget.

For example if the unique name of my authorize.net widget is "p" then I can successfully pass url parameter which radio button subscription to select (if multiple subscriptions are set up). i.e. p[][id]=1000

However, when I try to pass the parameter for number of recurring payments with the name of the dropdown defined as "custom_recurringtimes[1000]" I would need to drop the custom_ and only use "recurringtimes[1000]" and set the value some number. That does not work. I believe that the script that interprets the url parameters does not currently handle "custom_" prefixes. Can you please help? Also if it's possible can you let me know if there is a workaround. I want to specify number of payments via url parameter so that the user cannot change.

I checked your form http://www.jotformpro.com/form/80285709559974 and I'm afraid that the drop-down in the payment field is not possible to prepopulate.

Furthermore, even if the dropdown is prepopulated, I don't see a way to make it read-only (so the user cannot change it).

Those fields are part of iFrame (payment) which is hard to manipulate in that way from outside (of the mentioned iframe).