People talk about Delta calibration like it's some sort of impossible VooDoo. It's not. There's only two damn settings that really effect your major calibration.

Diagonal Rod Length and Centered Rod Offset. Those two settings may be called something different in different firmware, but they're always there and they always do the same thing. Diagnonal Rod Length will affect the dimensional accuracy of your printer and Centered Rod Offset (smooth rod offest, rod radius, horizontal rod offset, etc) affects the "dishing" of your printer. If Diagonal Rod Length is wrong then your printer will print things either too big or too small. If Centered Rod Offset is wrong then things don't get printed on a level plane.

The next thing in calibration is leveling. Which is dead simple. You level the effector plane with repsect to the bed by adjusting endstop offsets, or trimming them using screws that are sometimes mounted to the carriages (for some printers). 3 points define a plane. Your job is to make it match the bed. Takes 10 minutes if you have trimming screws.

I still think there's something fishy going on with your Repetier-Host and firmware. I can help you get them both to latest, which is ultimately the best solution.