My Vita is running FW 3.18 and has Unity 1.05 installed from a PKG back when it was still on 3.01 (update to that courtesy of God Of War Collection, updated further as Unity needed 3.15 as you know).
I've followed the PSM+ instructions to the letter as best I can several times, for example:
- Opening all the email files and closing the Email app rather than pressing OK when opening the attachements.
- Publishing Utility for Unity was used to grab the device info and generate the publisher key, device seed and app key ring. Twice, just in case the previous keys expired or something like that.
- All inputted to the app under Windows as the PSM Plus pages say to do here on Wololo.
Any advice would be appreciated because I've done a lot of steps to get to the right firmware version and all the rest of it and I still don't have much to show for it - I thought after five hours I'd make some headway but other than manually upgrading the firmware thanks to qCMA and installing Unity from a PKG I'd have cracked it, but so far I haven't and I wonder what I might have missed or done wrong. Thanks in advance.