All of the combination factors, K1 values (if timber design) and deflection limits can be edited at any time.
Although 'default values' are shown after the appropriate load case headings are selected, you can change any value to suit the current designs requirements. To do this, highlight the combination case 'row' - by clicking on any entry in the row - and then move the mouse pointer to the cell that requires changing.
After high-lighting the cell type in the required value (or use the scroll arrows) such that it is the value you need.
NOTE: Values that are edited in the chart are ONLY relevant to the current member.
All other members retain the combination factors etc, that were applied to them. If you want to 'permanently' create a set of combination rules, use the [Set Headings] option to create a combination header with the values required.
Note also, that change to header values DO NOT automatically change the parameters for member already added to the project. If yo do change the heading values, you must re-assign the header to the members effected.