Ok, update:
I now have a fully working iDeal script ready with a dynamic input field. In other words, place an amount (doesn't matter which type of field you create) and you will be redirected with the correct amount.
The problem now for me is intergrating this into the MPform. it's just a few lines of code but this is where I get lost.
Any help? Have the code available.
Greetz,
Boudi
UPDATE: Topic [
moved] to the DUTCH forum.