Just confirmed this isn't working. Worked fine in 10.0.0 but broke in 10.0.1 and 10.1.1. Login to the JSS via a web browser, click Computers at top left, then Management Settings at bottom left, then Configurations and pull up any configuration. Next, click Packages. The particular configuration I'm editing is called "macOS Sierra bare bones". The Packages window informs me there are 4 Packages. However, none of the checkboxes are checked and if I click to Edit, I can't turn on any checkboxes.
I just informed JAMF via a web chat so they are aware of this as a new product issue. The workaround is to edit configurations with JSSAdmin which works correctly.