We have created a parameterized lookup. The attribute is in the Investment Object and this attribute is added to the Idea blueprint, and when user try to select a value, it display an error "One or more parameters 'param_type_constrain" (or any other custom or an out of the box attribute which is referenced in the lookup as parameter) are not API-enabled. You may see unexpected results."
Attribute which is passed as a parameter is not API enabled.
Release : 15.9.1
Component : CA PPM SAAS STUDIO
Not all out of the box attributes will be API enabled, so as a workaround you can create calculated attribute pointing to an out of the box attribute and make that attribute API enabled and passed that custom attribute as a parameter.
This can also be caused by custom attribute which is referenced in the lookup as parameter that does not have an API alias.