I find it great, that other persons build it and find the same "problems".
But there are easy ways to solve some of them.
1) Rear lowershock position - To adjust the ride height in the same range, you have to use other/lower spring plate. So I used them from my old HB TCX (#73510). They suit perfekt and you can easy set for example 4mm ride height.
1.2) Shock position - The biggest problem is, that the lower shock attachment ist much more inside the car and the shock has another angle, so that you have a complete different spring and shock transmission. I calculate a little bit and get a correction factor of 1.17. So your old spring hardness multiplied with 1.17 result in the spring hardness, which you have to use with an active suspension. Also you have to use harder oil. Concrete it means, if you use for example the Spec-R 2.5 Spring now you have to use the 2.9 Spring and instead of 350cSt oil you have to use 400cSt to have comparable values.
2) Rear roll bar - Here the same. To get nearly the same values, you have to use a correction factor of 1.26. So your old diameter divided by 1.26 result in your new diameter of the roll bar. So instead of the 3 point rear roll bar you have to use the 1 point front roll bar.
The biggest problem ist, that the roll center values also changed and
I have no desire to calculate that one too
and i´m not 100% sure if my calculates are general right.
But we will see it next week and i will give you an detailed report