Using Fusion to create a Planning entry from an issue and mapping custom field values

[ChristianSi6]

We just licensed Planning and I'm trying to create Planning entries from issues.  I have been able to do it at the most basic level but I get errors when trying to leverage custom form fields from the issue and put those values into the Planning entry.

The fields I'm having problems with are either single- or multi-select dropdowns in the issue and the text values are the same in Planning but are built as custom columns in Planning rather than records.  Trying to map the values from the custom form fields into the fields for Planning yields the errors below.

I understand these are two different object types and (as far as I'm aware) custom forms aren't supported in Planning quite yet, but has anyone tried this and been successful?