v7.15.3 [stable] is released!

The same error message does not necessarily mean the same error. This particular error message says that execution of the script has ended prematurely due to some error inside the script, but the change of the package name from system to routeros is just one of many possible errors in your script that may have been caused by a version change - some parameters may be renamed, some missing…

So you have to debug the script as if you were writing it from scratch, spawning it manually and adding debug prints (:put) to isolate the row encountering the actual error.