Generative Design is a feature of Revit which helps find optimized solution for design problems by way of Dynamo. Read up on it here: https://www.generativedesign.org/
Fortunately that warning is only saying there isn’t a /dyf folder in the package, which is by intentional so you can ignore it. (FYI @achintya_bhat @solamour @emrullah.yildiz might want to consider shipping an empty .dyf folder to prevent this from or otherwise repress the warning another way)
Then you may have a conflict between Archi-Lab and a Revit add-in. Disable ALL Revit add-ins and try again.