Find "Assisted Install.txt" in your trial version, then change licence key to yours.
Ye, that's what I thought, but couldn't find that file.
I've managed to get a copy now though, so panic over ;-)
On Windows installer extracts files then ask language, you should cancel the installation. The file is in FMICD\files folder. Edit it then run extracted FMICD\Setup.exe, not use downloaded fmptrial....exe any more.
Do you use Mac?
We are on Mac but we've managed to get it sorted now thanks.