When is your microflow triggered, is this after or before commit ( it should be after commit).
Also, try using a change object operation rather than a change list. Use the add option instead of set, this will make your microflow a bit smaller in the process.
Just out of curiousity how do you know which Object2 to set? Do you create a new one when you create Object1 or do you have a relation between Object1 and 2?