Thank you very much for this explanation. I also found it very useful for me. However, I want rise couple questions.
First of all, what about wstate array for CASSCF and XMCQDPT?
Or more simpler, where and what should i look in an output file to find contribution of CASSCF states into XMCQDPT states? Also, i saw a lot of posts about analysis of CASSCF part, but for me it is steel "pitfall". For example, for CASSCF(4,4) first state has main (coef~0.9) configuration 2200. But second 2020 (coef~0.9). Does it make sense for UV spectra? For me more natural configuration would be 2110 or 2101. Should we consider such state (2020 or 2002) for construction of wstate array for XMCQDPT? I would be very appreciate for any explanation of my questions.