As an old QB45 business coder, I can tell you I never liked or used "CHAIN" in any of my apps. Much like you, I had several programs that needed to interact with each other, so I just sent the variables to data file, and had the new program load them. Simple and worked like a charm.
Another alternative is to take advantage of QB64 memory, and just combine all those programs. That's no small task, but that's what I ended up doing. It gave me one 80,000+ lines of code and it was during the time Rob was developing QB64, so it helped with beta testing. Those were exciting times.
Pioneer Pete