awesome thank you for your suggestions all! my final solution::
a "note clock" jsfx (attached) i found here in the forum. nice in that it lets you use time instead of beats as well as let's you unlink from the transport (via it's "run constant" parameter). i set it's "period in seconds" manually to something like 10000, and then put the stock jsfx midi delay after it (delay ms set to 1000). and then minihost modular after all that. so when i start up reaper, the midi clock fires off the note (you need the delay jsfx or the note gets missed somehow on startup), and the note triggers piano looping piano rolls/cc automation lanes/vstis inside minihost modular. this has worked great for generative installation/live performances using reaper.
the midi note length jsfx is useful if you want the clock to send pulses. putting a random lfo on the clocks time makes for some interesting experimental things to happen.
link to minihost modular - a really great, not well known freebie:
https://www.image-line.com/fl-studio...odular-beta-3/