@judym Hi, here are a few suggestions as per my review so far, and I hope these would help you to some extent in order to sort the issues in the interface definitions attached:

1. I think there is a problem with usage of local!roles variable in the below dropdown component. I guess it should be as follows, commented the lines where I have made the changes.
a!dropdownField(
        label: "Employee Role",
        choiceLabels: local!roles.data.roleName, /* Changed */
        choiceValues: index(
          local!roles.data, /* Changed */
          "id",
          {}
        ),  
        placeholderLabel: "---Select User Role---",
        value: ri!newTeamLink_cdt[ri!index].roleId,
        saveInto: ri!newTeamLink_cdt[ri!index].roleId,
        required: true(),
        readOnly: false()
       ) 
	   
2. For any dropdown component I would like to suggest to perform a null handling as follows for the 'value' attribute:
value: if(rule!APN_isEmpty(ri!newTeamLink_cdt[ri!index]),null,if(rule!APN_isBlank(ri!newTeamLink_cdt[ri!index].userId,null,ri!newTeamLink_cdt[ri!index].userId)))
I don't think there is an error at the moment, but to the best of my knowledge if existing issue in the interface is sorted, the next error would be related to null values in ri!newTeamLink_cdt[ri!index].userId and ri!newTeamLink_cdt[ri!index].roleId and above is the way how you can handle them


The errors you specified:
 ips_assignUserRolesMain – In this one I get the following error: 
Could not display interface. Please check definition and inputs. Interface Definition: Expression evaluation error in rule 'ips_assignuserrolesgrid' at function a!applyComponents [line 88] - I guess this could be sorted indirectly when the above changes are done and might be some more on need basis are made as per other's observations and when ips_assignUserRolesGrid is up and working.

ips_assignUserRolesGrid – In this one in the Interface Designer, I get the following error:
Could not display interface. Please check definition and inputs. Interface Definition: Expression evaluation error at function 'index' parameter 3 [line 31]: I can't figure out what is wrong with this rule. - I guess the suggestions 1 and 2, and may be other practitioner's suggestions should solve the problem in this rule.

Further I didn't understand the intention behind datasubset conversion that has been done for local!users and local!roles. I guess it's not needed. Anyhow this isn't relavant to the issues you are experiencing currently.