When adding a formula in a type paramater, if that referes to an instance parameter it will (correctly) prevent the relationship. This presents a dialog popup and then the user needs to manually go to the conflicting paramater and change the relevant family type/instance to be compatible.
In that dialogue that warns of the conflict - Add buttons to "convert $InterferingTypeParamater from Type to Instance" and "Convert $InterferingInstanceParameter from Instance to Type" to more quickly resolve the conflict for the user. Either option may be desireable.
Retain the "cancel" option if the user wants to dig in manually.
This may need a "This change will impact the following parameters ...." warning where it's necessary to convert more than one level of nested logic, or a "Multiple paramaters are in confliict and automatic conversion is not available" option.
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