There are some things that wont work in tws that work for CA7
in ca7 you can have jobs that dont actually have jcl but point to other jcl
in tws the jobname must match the jobcard so this wont work
in ca7 ca11 will clean up temporary files, for tws every job requires a scartch step or the next time it runs it will fall over with a duplicate dataset error
One thing to watch out for during the conversion is when generating applications if a job is used in more than one application and defined as a predeccesor it might incorrectly reference it for every application it occurs in, giving you multiple predeccors.
These are only minor things that dont really impact much once you catch them, in all our conversion went pretty well. Good luck