Reply to Has anyone successfully booted to 1.2 fw from 1.4?

I want to try using my VCI-100 with other software (mixxx). It's been well documented that firmware 1.3 can boot into 1.2, and I have seen that you can *supposedly* do it with 1.4. I haven't been able to however -- and I have seen other reports that other people cannot. (for example, one of the first hits from google is a youtube video of someone trying this and failing) So...

(1) has anyone actually booted into 1.2 from 1.4? Any "tips" on doing it properly?

(2) If not, has anyone successfully *downgraded* to 1.3 in order to get 1.2 working?

Thanks. Apologies if this is redundant, but it's not easy to search the community for this.