There are 2 possible main scenarios: if the modifiers for the moments of inertia to be assigned to all active labels or modifiers for the moments of inertia to be assigned to selected labels only. 

First scenario

1. Create a table with the predefined modifiers for the moments of inertia based on the ACI 318 by pressing the button Create Template. All values in the table can be adjusted if required.
2. Press the Assign Modifiers button and modifiers from the table will be assigned to all active labels in the model based on the member type (beam, column, slab, and wall). Only RC sections are supported. Beam and column types are recognized automatically based on the label type. Homogeneous slabs and walls have the same label type and the first symbol in the label name is used for the separation. It is assumed that slab labels start with “s”, “S”, “f” or “F” (e.g. s200, F_250, floor 230) and wall labels start with “w”, “W”, “c” or “C”. It is possible to add additional markers to recognize slab and walls. User can indicate the marker character for walls in cell A1 and for slabs in cell A2.
3. In case if the modifiers are already assigned to the labels, modifiers will be multiplied by values specified in the table by pressing the button Multiply Modifiers.
4. The button Switch Off Modifiers will deactivate modifiers for the moments of inertia for all active labels

Second scenario

1. Create a table with the existing modifiers for the moments of inertia for all active labels in the Robot model by pressing the Get Current Modifiers button. 
2. Change modifiers for selected labels. Make sure that empty rows deleted from the table. In case if some labels should not be changed, delete these rows.
3. Press the button Assign Modifiers Label Based to apply changes 

Download the installer from the Autodesk App Store 'IModifier.exe'

To install the app double click on the downloaded installer and follow the instructions.

To uninstall this plug-in through Control Panel > Programs > Programs and Features (Windows 7/8.1/10/11) and uninstall as you would any other application from your system.