Here is Blocs 3.2 Beta Build 7, this release is again mainly focused on bug fixes. Aiming for release later this week, so any last fixes required will most likely be rolled into the main release version unless they are super complex.
You can now create modals (popups) here is how you make them.
Add a modal bric to the page, make sure it has an ID.
Select a button, link, icon or image and set its interaction to modal and then find the target modals ID in the second dropdown below the interaction one.
Enter preview mode and you will see the modal is hidden and will be shown when you click the trigger you assigned the modal interaction too.
You can now hide the entire Blocs UI apart from the menu bar at the top. There are various ways to do this,
The main menu view > Interface contains options for hide/show them (includes keyboard shortcuts).
Right clicking the sidebar tab area at the top of each sidebar gives you options to hide them.
Right clicking on the design canvas, under the interface option on the context menu.