The CheckAndModifyPropertyValueTask is used to modify properties of nodes that might be already not present (due to user changes). In such situation, it causes an installation/update error - but many times such missing node is not a reason to abort the module installation/update.

I suggest to add new constructor with a boolean strict parameter, that will indicate whether an error (if true) or just a warning shall be issued in case that the specified node is not found. The current constructors will call the new one with the strict parameter set to true, to keep the current contract.