diff --git a/Writing-an-Op-Mode-with-FTC-Blocks.md b/Writing-an-Op-Mode-with-FTC-Blocks.md
index 927f6d7..3b18c04 100644
--- a/Writing-an-Op-Mode-with-FTC-Blocks.md
+++ b/Writing-an-Op-Mode-with-FTC-Blocks.md
@@ -58,7 +58,7 @@ When the Robot Controller reaches the block labeled “call MyFIRSTOpMode.waitFo
 
 <p align="center"><img src="https://github.com/FIRST-Tech-Challenge/WikiSupport/blob/master/ftc_app/images/ExaminingStructurePic4.jpg" width="300"><p>
 
-After the “call MyFIRSTOpMode.waitForStart”, there is a conditional "if" block that only gets executed if the op mode is still active (i.e., a stop command hasn't been received).  
+After the “call MyFIRSTOpMode.waitForStart”, there is a conditional "if" block ("if call MyFIRSTOpMode.isActive") that only gets executed if the op mode is still active (i.e., a stop command hasn't been received).  
 
 <p align="center"><img src="https://github.com/FIRST-Tech-Challenge/WikiSupport/blob/master/ftc_app/images/ExaminingStructurePic4bControlhub.jpg" width="600"><p>
 
@@ -75,6 +75,10 @@ In this section, you will add some blocks to your op mode that will allow you to
 
 Note that you will need an estimated 15 minutes to complete this task.
 
+Important Note: The programming blocks for user configured devices (motors, servos and sensors) will only be visible in the Blocks tool if there is an active configuration file with the configured devices included in the file.  If a type of device is not included in the active configuration file, then its programming blocks will be missing from the palette of blocks.
+
+If you did not (create and activate a configuration file yet)[https://github.com/FIRST-Tech-Challenge/ftc_app/wiki/Configuring-Your-Hardware],then you should follow the (instructions in the wiki)[https://github.com/FIRST-Tech-Challenge/ftc_app/wiki/Configuring-Your-Hardware] to do so.  After you created and activated your configuration file, you can close and then reopen your op mode so that the programming blocks for the newly configured devices will be visible.
+
 | Modifying Your Op Mode to Control a DC Motor |
 | ---- |
 | 1. On the left-hand side of the screen click on the category called “Variables” to display the list of block commands that are used to create and modify variables within your op mode.<br/><br/><p align="center"><img src="https://github.com/FIRST-Tech-Challenge/WikiSupport/blob/master/ftc_app/images/AddingDCMotorStep1.jpg" width="200"></p>Click on “Create variable…” to create a new variable that will represent the target motor power for our op mode. |