Hello and welcome to our forums,

"Is it possible to have an option dialogue to show different versions that users can select a version to install?"

Yes, this is possible. You can achieve this by creating a new dialog, placing some checkboxes on it and then conditioning the installer of the components based on the checkbox state.

Here is a step-by-step way you can follow to implement it:
1) Go to "Dialogs" page from the "User Interface" group and create a new dialog using the "New Dialog" button from the toolbar.

2) Now using the "Control Toolbox" button from the toolbar, add as many "CheckBoxes" as you need. Please keep in mind that each checkbox will coincide with each of your versions.

3) After that, click on your first checkbox and a "Properties" tab will appear in the right pane. Let's change the property name so it'll be something more intuitive, for example VERSION_1_PROP.

4) Do the same for the rest of the checkboxes.

5) Now that we have created the checkboxes, we must condition the installation of the components (your versions of the application) based on the checkboxes states. To do that, you can go to "Organization" page from the "Package Definition" grup, select one of your components, let's say the first version of your application and in "Condition" field, type the following condition: 6) Do the same for the rest of your components. This way, you have conditioned your versions to install only if the checkbox from the earlier created dialog are checked.

Hope this helps!

Regards,
Catalin