@dvdsnyd
I think you can use stratos simulator even for high power rockets with drogue chute and main parachute.
You have to use it two times for two different computations.
Let's say you lift-off from 800ft AMSL (location A),
go up to 60,000ft,
deploy the drogue chute and descent at 30m/s
to predefined alt. 10,000ft.
Then use the main parachute (descent speed 5 m/s) from loc. C
to landing zone.
Stage 1.
Lift off of imaginary location A1 at 10,000ft, and "land" at loc. C.
Use max. possible ascent rate and drogue's (relatively fast) descent rate.
Stage 2.
By using loc. C1 as lift off location (elevation 800 ft), predefined 10000ft as burst altitude
and parachutes (relatively slow) descent rate
you can have a computation of landing location.

See drawing.
399b0bae-d428-4bb0-88a9-05c3fd6c9150-εικόνα.png