We can allow calling a script from a different script in the API.
We hesitate doing that because pausing the first script for the duration of the second is actually not easy. Our scripts can spawn threads, they will all have to be paused / resumed, this has to be coordinated. Plus the longer the pause is, the more potential trouble it is, because who knows how much the state of the data will deviate from what it was at the moment of the pause - if it deviates enough, resuming might fail spectacularly. Plus the second script will then be able to invoke a third script, this all is going to be a stack. Long story short, we hesitate allowing scripts to call other scripts because, if done properly, this is fairly complex, so we'd rather try other things first.
From your description, might it be that you will be fine with means to include a script into another script? Ie, you'd write script 1 with some utility functions and without Sub Main, then you'd write script 2 and write something like:
' @include [script 1]
...and that would allow you to call functions or subs that reside in script 1 from your code in script 2.
Is this essentially what you are looking for?