When trying to view concrete column design results (or trying to report them), the following error can appear which prevents the report from appearing and cause the module to terminate:
RAMConcreteColumn - Encountered an improper argument.
Make sure the combinations are valid.
1. Go to Combinations - Generated... and make sure the desired cases and combinations are listed and checked.
2. Go to Combinations - Custom... and if there are any invalid combinations (which appear in red) make sure they are unchecked, or delete them.
Custom combinations can become invalid if the types of loading in the model changes. In the case above, the loads we toggled from Snow (Sp) to Roof Live loads (Rfp), for example.