I'm wanting to use the preconfigure tool, however it doesn't preconfigure for 10Mhz channels. Looking at the JSON the preconfigure tool creates I assume the setting is this setting:
You are right, scan_chanbw is parameter which controls bandwidth selected for scanning. 3 is default value for 20+40 MHz. 1 - 20 MHz, 2 - 40 MHz, 4 - 5 MHz, 8 - 10 MHz, 15 can be used for 5+10+20+40 MHz. It is binary mask so you can easily calculate needed combination.