First, check to make sure you have security turned on. Use the lawsec command without any parameters to check. Are you using LAUA security or LS security? If LS, do you have "security checking" turned on in Security Administrator? For this user, do you have the CheckLS flag set to YES or NO?
You need to remove securable type FORM. It intersects with system code to allow access to any form in an allowed system code.