Hi Gang,
Thank you so much for looking over this so quickly! I made the change and for some reason, I keep getting the same error. I checked for typos a couple of times, and also tried the code with a single GLT (in which case, I get a different error: "Error in outList[[1]][[n]] : subscript out of bounds | Calls: process.MVM.opts -> gl_Constr"). I tried putting the sub-brick indicator in the data table in quotation marks '[1]' instead of [1], which still didn't work. Let me know if there is something else to try - and thank you so much again for your help!
Irena