You are so close. Your efforts are much better than others that have posted here, asking for help without even having tried to write any code at all. I don't have LV 8.5 so I can't make corrections and send it to you. Because you made a good effort, if I had 8.5, I would make the corrections for you. But since I just have 2009, I will try to explain what to do.
First, you should create a while loop at the beginning of your code. Put the Start Process control inside the while loop. Wire the control to the stop sign. Also wire the control to the flat sequence structure, through the wall of the while loop. Add a delay inside the while loop with an input of 100. Here is what will happen. The loop will run every 100mS. As long as the Start Process is not pressed, the loop will run again. When the button is pressed, the loop will stop and the button data will go to the flat sequence. The flat sequence will not start until it sees the button data input. To see this, turn on the light bulb and watch the execution flow. The 100mS delay is a good idea so that the CPU time is not being used 100% by Labview.
Since the Start Process data will be true when the flat sequence starts executing, the pipes and valves specified in the first frame will all turn on. In your original VI, if you ran the program without first pressing the button, the valves and pipes were all off. Now the first frame will execute, and the loop will continue until the mixer is full. If you want to shut off some pipes and valves at this point, right click on the ones you want to shut off and select Create - Local Variable (you must do this one at a time). Put the local variables in frame 2. Wire a False constant to each one. Put this before the loop in frame 2. This will turn off the items and then the loop will continue until the product tank is full. If you want the mixer to empty as the product fills, create a local variable for the mixer and put it in frame 2 while loop. Subtract 100 - i and wire the output to the mixer local. This will cause the mixer to empty as the product fills.
At the beginning of your code, you should return all pipes, tanks, and valves to the default (off or empty) state. Look in the Application Control palette and select Invoke Node. Put it on your block diagram before the new while loop you created for the Start Process button. Wire the error out to the while loop border so that it can execute first. Point to the word App in the top half of the Invode Node, right click and select Select Class - VI Server - VI - VI. The word App will change to VI. Then point to the word Method in the bottom half. Left click and select Default values - Reinitialize all to default. Now when you start your program, all controls and indicators will go to the default state.
If you need further help, just ask.
