independently control multiple channels of a power supply

Given

• Keithley 2230-30-1 triple channel power supply
• necessary drivers

I've installed the Instrument Drivers and can control the device using the example VI provided by Keithley pictured below.

Unfortunately, I can only control one channel at a time. Say I set channel 1 voltage to 15V. When I switch to channel 2, the VI sets channel 2 voltage to 15V as well. If I change the channel 2 voltage to a desired voltage, say 7V and then switch back to channel 1, then the VI sets channel 1 voltage to 7V too. So I decided to make my own simple control VI pictured below.

Problem

my VI sorta won't work.

• When I run continuously, I get the error below which I know is because I'm not "concluding" the bottom threads that control channel 1.
• When I run with highlight executions, my VI works, albeit slowly.

Questions

1. What gives? Why does the VI work in debug mode but not normal?
2. Can I merge VISA resource names? I feel such a feature would enable me to "conclude" the bottom thread's VISA wire much like a conclude error bundle.
3. Better yet, what's the proper way of wiring what I'm trying to do?
   I feel like my program doesn't work because I'm asking the PSU to read/write at the same time. Would placing channel 1 control and channel 2 control in sequence structures with 0 programmed delay enable me to "simultaneously" and independently control the 2 channels?

Many thanks!