I have it on my PSP 1K running 5.50 Prometheus and it works fine. No idea which version it is 'cause I got the link from a youtube vid if memory serves, but the filesize is 164MB for me and it shows no problems.
And the Harvest Moon games are fucking fantastic, don't let anyone tell you otherwise. If you haven't already, look into 'acquiring' Harvest Moon Boy+Girl for your PSP. It's Friends Of Mineral Town and More Friends of Mineral Town (the female version) fused together using the old PS1 game graphics. It'll cost you about 70MB give or take, but aside from a few slowdown issues (the game slows down when you go past the church but nothing serious, just irritating) it runs perfectly. I have mine on UMD but I'll be downloading it later because the UMD is on its last legs, already had to glue it back together twice.