Hi jo
When I changed from 32 bit to 64 I had back ups.
When I reinstalled some programs I had 6 terragen exe's in my programs for some reason so I deleted all but
the newest.
When I tried an update I kept getting the error in (1st post pic)
So I removed all terragen from my computer and reinstalled from scratch all was ok then I got the update message
hit it installed for 64 bit but had no color picker (but worken on 32 bit)
after going crazy and uninstalling reinstalling many times and some system restore still had the same problem
then using the show key file it took me to App data in a file called planitside,uk, inside was license key and color picker data
so I shredded it whole file and all terragen files reinstall terragen 64 bit added licence key and now all works great
Was a long time but all is ok now

thank you