Here you go. I fear that your database may be suffering from lack of normalization for you to have so many check boxes. I didn't want to look at your relationships.
Nevertheless, I have made some amendments to the layout and also to the long names you have for each tab. You can have short names and use the ControlTip Text and Status Bar Text properties of each page to display the long names. Hover over your page and you will see the ControlTip Text pop-up, also look at the status bar and you will find the long name. You will notice I decreased the font size of the names as well. That can be done via the Tab Control itself.
You need to know how to select your subform, tab control, and page for you to understand how to properly layout your controls and forms.
For your check boxes, the name doesn't need to stretch out full-length for it to be readable. The caption wraps just like in Excel when you set a cell to wrap. When you're using tabs it's best you use the same width (and height if possible) of your subforms in design view, that is the grey area, and also the same width and height (must) for each subform control on each page. Then you can minimize your Tab Control so it doesn't overspill.
Hope this helps!