Export Time Domain results using lua script

Hi,

I have a  time-domain excitation pulse (generated using Matlab as a .txt file). this excitation needs to be imported to PostFeko, calculate the time domain voltage across the load (in postfeko), then export the TD voltage to .dat or .txt file. I need to run all of this through Lua script. If I can do so then instead of reopening postFEKo every time I change the excitation pulse I can run the script through Matlab.

I have attached a basic Lua script that reads the current across the load and exports the data to the .dat file. However, it exports the Frequency domain data, not the Time domain. I have a very very basic knowledge of LUA scripting. I would really appreciate it If anyone has an idea of how to modify the script to perform the above tasks.

attached the FEKo Files and the Lua script.