Hi Chris,

Yes, you can
For the floor, you can use the Add points feature. You will find the Add / Delete Points icons in the Snap bar (right of the screen - see attached)
You can add points to almost any Punch shape and element
However, you can't add points to curved shapes (you can straight them--> add points--> adjust the curve again). You can't add points to Punch's ready elements (ready hip roofs, for example)
Special Objects (windows, doors, etc) don't accept new points

As for the walls, you can add new points or use the Break wall tool (Floor tab--> 6th icon from the left)

Hope this helps

Patricia