Changing a Mid-Sequence Icon in the Vantage Lite.
This feature allows you to label keys within a sequence. Although it is called Mid-Sequence Category, you can use it in sequences of any length.
Let’s look at a specific example using the Unity 144 available in an ECO device.
All FOOD vocabulary starts with the 
and a second Core icon represents a sub-category. So, the following examples show five categories of FOOD.
Using Mid-Sequence Category, it is possible to add a label to the second icon in the sequence.
You can also add a category label to the first icon of a sequence.
Finally, the Mid-Sequence Category feature lets you change the icon.
Steps for storing Mid-Sequence Category tool: 
1. This key will be a temporary tool that you store in the user area, use it for making prompt labels, and then delete the tool.
2. Find a blank key in the top row by selecting Choose Activity,
3. Use the Set-up key, and then select a blank key in the top row (activity row)
4. Assign this key as a Tool
5. Select Enter Assignment
6. Select Spell Message or Define Key Function
7. Select Insert Tool.
8. Select Mid-Sequence Category
9. Select OK. OK
Storing a Mid-Sequence Category
This feature is just a special type of STORE operation. You use it by using the MID SEQ CATEGORY key instead of a STORE key. This means that the first thing you have to do is make sure you have the MID SEQ CATEGORY tool assigned to a key or sequence on your overlay which we did above. Once you have assigned it, here is the procedure for storing FRUIT in the APPLE + FLOWERS + ICON set.
1. Select your MID SEQ CATEGORY key.
2. The prompt Enter a Partial Sequence appears.
3. Select the keys to get to the one you want to label – in this case APPLE + FLOWERS.
4. Select OK.
5. You see the prompt Modify key as needed, then select OK, and the actual key.
6. Select Change Label, type FRUIT, then hit the OK button.
7. Select the OK button at the bottom of the page and the operation is complete.
Note: Turn Mid-Sequence Category Prompts on or off in the Feedback Menu in the ToolBox.
Tip: When you are finished storing, clear the key contents of the temporary Mid-Sequence Category tool in the activity row.