Óscar Toledo Gutiérrez is one of the best coders in the MSX/Coleco scene. Remember his great contributions to MSXdev' contests : Mecha Eight - Zombie Near.
He has also created Princess Quest, but until now, it was only available on cartridge for MSX and Coleco. As the Coleco version is sold out, he has decided to make this version available in digital form for a reasonable price.
http://www.scubbly.com/item/77635/You need only to pay 9.95 USD (something like 7.20 €), the payment is really fast with PayPal and you receive also very fast a link to the file in your mail program !
To play the game, you need blueMSX 2.8.2 or higher, select a Coleco machine, insert manually the rom (256 kb) in a cartridge slot and select the Colecovision Megacart mapper.
NB. I don't know if there are plans for a future digital MSX version. As I have now acquired the Coleco digital version, I will not buy an eventual future MSX digital version. Anyway, the Coleco version is probably better !