It is great fun to plan, import and analyse data in Memory-Map. The problem is that things can quickly become cluttered and overwhelming. The key is to make sure you do some "housecleaning" early and often.
The first priority is to ensure you have a backup copy of your data. This is easily accomplished by going to Overlay > Export All.... Then, select a location and give the file a name. You will note that the program defaults to our MMO file format, but you have the option to select other formats.
Sorting your data
This is great for saving a full set of data, but as mentioned before, this can quickly become overwhelming. To organize your data more efficiently, you will have to sort it into categories.
To create a new category/subcategory, move your cursor over the Overlay Object side bar, right-click and select New Category. (If you right-click on an existing category, a subcategory will be created under that category.)
You can now drag and drop routes from another category to the new category. If you have to move the category up/down beyond the visible section of the Object window, you can use the arrow keys on the keyboard to navigate the window.
Saving overlay objects/categories
In order the keep your overlays manageable, you will want to save them in smaller groups. To save an individual overlay or category, right-click on the object/subcategory/category and select Save as.... You can create as many MMO (or other format) files as you need to keep your data workable. Ensure that your file names are adequate to allow you to identify what is inside. Saving files such as Routes1, Routes2, etc. will not be very helpful in the long run.
Once you have saved this data, you will want to clean it off of your computer to make room for new overlays. You can do this for objects, subcategories or categories by right-clicking it and selecting Delete If you have saved all of the overlays you want to keep, you can also go to Overlay > Delete all... in the toolbar and delete all of the current overlay objects. You will also see the option Delete Hidden....You can use this, along with the Overlay > Show All and Overlay > Hide All options to hide or show overlay objects. (Please Note: These options hide or show all overlays in the selected category, not just the ones shown on the current screen.) Once hidden, you can use the Overlay > Delete Hidden... option to delete the overlays you have hidden.
To load data saved to a file, you can simply double-click on the file. This will add the overlays contained in that file to the existing overlays in your overlay list. If you want to start clean, then save the existing data in the program, delete all, and load the new file. Optionally, you can use the Overlay > Import... option in the toolbar to load a file.