Okay, this is fun: I discovered the answer to my own question! TT usually runs in step-by-step mode (Question prompts that you answer), and that is where the problem is: you can't reset it to get to the right step again. The solution is to do your best to finish up your Federal and State taxes outside of the problematic areas, then select the menu option "View" and go into "Forms", where it lets you make entries into each of the forms on your state and federal returns. You can directly access the Ohio Medical Expenses Worksheet and enter what you need to . You can also return to the federal medical expenses area and enter new costs (this was also an area that "locked" after my first inaccurate entries...).
NOTE: TT will send some of that federal medical expense info into the Ohio forms, but it does NOT parse the different categories of eligible expenses accurately for the Ohio regulations. Fortunately you can enter the Ohio values independently for most categories.
