On the Send tab
Probably your are misunderstanding S2, S2. They don't send strings, they just load the editboxes https://realterm.sourceforge.io/#Command_Line_Parameters I can't use Win10 at present, but possibly permissions need to be changed, or perhaps the ongoing security changes have broken interwindow comms. You don't seem to be needing to do it anyway, in the example batch file.
https://skilldrick.github.io/easyforth/ https://el-tramo.be/waforth/ https://brendanator.github.io/jsForth/
Most things are on the website. Don't forget this: (V3.0.0.27+) The DoCommands method makes all commandline parameters available to ActiveX/COM user. If the ActX lacks a command, check the commandline. The commandline has had more things added to it that the COM interface in recent years.
Don't strings have some sort of quotation symbols around them?
Direct capture checkbox is about this https://realterm.sourceforge.io/#Capture
Off the top of my head, sending files is done directly, and doesn't involve the terminal. So probably not a simple change.
I might make this have a binary flag param i.e. CR=1 does the same as present CR=3 sets both. (when I get around to the next update)