Yes the glue will dry clear. It will turn slightly cloudy if you have a lot of rain, but will clear up again. I have some ballast glued down from last year and it is still looking good.
I mixed 50/50 glue and water and added a couple of drops of dishwashing liquid soap. This is to break the surface tension of the water. I poured mine on but next time will try spraying it on. You could pre-wet the area with water and soap first before adding the glue mixture.
Edited by: Dennis Cherry