1) answer no to letting Illinois compute your penalty - then continue
2) answer the exception questions then continue or just continue
3) enter prior year amounts then continue
4) now you are at the underpayment penalty page where you answer yes to the question stated.
you now can complete the entry of the AI info.
Unfortunately, that did not work.
To enable the the "Step 6: annualization worksheet" I had to enter erroneous data to force a under payment penalty (originally I was due a refund, but IL would have charged a penalty due to the timing of my withholding). Once the erroneous data was entered the "Step 6: annualization worksheet" became active. I then could complete "Step 6: annualization worksheet". Then I went back to delete the erroneous data and printed out 2210-IL (which remained active after the erroneous data was deleted).