In Irish Gaeilge:   Ta grá agam duit or Táim i' ngrá leat. (different dialects/ways)

In Scots Gaelic:   Tha gràdh agam ort.


Have fun with the instruction, Skarpi. Sounds like a day I'd enjoy a lot, myself.

By the way, have you seen this movie? When it was released on videotape over here, it was called "The Celt". The costume and weaponry was supposed to have been well-researched anyway.