I enjoyed it but did I do have some suggestions.
1) Having a grid so I know how far I need to go
2) Being able to "lock-in" to a puzzle so you can use your up (and down) arrow key to bring up previous entries and then left/right arrow keys to be able to move through your runes to fix a mistake
(or)
3)Having the path be drawn as you type in the runes. Because right now you either have to enter in the runes over and over, slowly making it longer a few runes at a time or figure out the whole sequence in your head (which I did because I found the other way annoying, especially since the runes didn't line up to the previous ones so it was harder to re-enter)